Method and apparatus for performing psfch transmission in nr v2x

ABSTRACT

A method for a first device to perform wireless communication is proposed. The method may comprise: receiving at least one physical sidelink control channel (PSCCH); receiving at least one physical sidelink shared channel (PSSCH) related to the at least one PSCCH; determining a resource related to at least one physical sidelink feedback channel (PSFCH) based on an index of a slot and an index of a subchannel related to at least one PSSCH; determining N PSFCHs from among the at least one PSFCH based on a sum of power required to transmit the at least one PSFCH being greater than a maximum transmit power of the first device, wherein N is selected from a number of PSFCH transmissions with high priority among a maximum number of PSFCH transmissions, to the maximum number of the PSFCH transmissions.

CROSS-REFERENCE TO RELATED APPLICATIONS

Pursuant to 35 U.S.C. § 119(e), this application is a continuation ofInternational Application No. PCT/KR2021/005038, with an internationalfiling date of Apr. 21, 2021, which claims the benefit of U.S.Provisional Patent Application No. 63/013,511, filed on Apr. 21, 2020,U.S. Provisional Patent Application No. 63/014,693, filed on Apr. 23,2020, U.S. Provisional Patent Application No. 63/016,271, filed on Apr.27, 2020, U.S. Provisional Patent Application No. 63/025,877, filed onMay 15, 2020, U.S. Provisional Patent Application No. 63/027,933, filedon May 20, 2020 and Korean Patent Application No. 10-2020-0051642, filedon Apr. 28, 2020, the contents of which are hereby incorporated byreference herein in their entirety.

BACKGROUND OF THE DISCLOSURE Field of the Disclosure

This disclosure relates to a wireless communication system.

Related Art

Sidelink (SL) communication is a communication scheme in which a directlink is established between User Equipments (UEs) and the UEs exchangevoice and data directly with each other without intervention of anevolved Node B (eNB). SL communication is under consideration as asolution to the overhead of an eNB caused by rapidly increasing datatraffic. Vehicle-to-everything (V2X) refers to a communicationtechnology through which a vehicle exchanges information with anothervehicle, a pedestrian, an object having an infrastructure (or infra)established therein, and so on. The V2X may be divided into 4 types,such as vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I),vehicle-to-network (V2N), and vehicle-to-pedestrian (V2P). The V2Xcommunication may be provided via a PC5 interface and/or Uu interface.

Meanwhile, as a wider range of communication devices require largercommunication capacities, the need for mobile broadband communicationthat is more enhanced than the existing Radio Access Technology (RAT) isrising. Accordingly, discussions are made on services and user equipment(UE) that are sensitive to reliability and latency. And, a nextgeneration radio access technology that is based on the enhanced mobilebroadband communication, massive Machine Type Communication (MTC),Ultra-Reliable and Low Latency Communication (URLLC), and so on, may bereferred to as a new radio access technology (RAT) or new radio (NR).Herein, the NR may also support vehicle-to-everything (V2X)communication.

FIG. 1 is a drawing for describing V2X communication based on NR,compared to V2X communication based on RAT used before NR. Theembodiment of FIG. 1 may be combined with various embodiments of thepresent disclosure.

Regarding V2X communication, a scheme of providing a safety service,based on a V2X message such as Basic Safety Message (BSM), CooperativeAwareness Message (CAM), and Decentralized Environmental NotificationMessage (DENM) is focused in the discussion on the RAT used before theNR. The V2X message may include position information, dynamicinformation, attribute information, or the like. For example, a UE maytransmit a periodic message type CAM and/or an event triggered messagetype DENM to another UE.

Thereafter, regarding V2X communication, various V2X scenarios areproposed in NR. For example, the various V2X scenarios may includevehicle platooning, advanced driving, extended sensors, remote driving,or the like.

SUMMARY OF THE DISCLOSURE Technical Objects

Meanwhile, in NR sidelink communication, when the UE performs at leastone PSFCH transmission, and the power of the UE is limited (e.g., thesum of PSFCH transmit power required for the UE exceeds the maximumtransmit power value of the UE), the UE may have a problem regarding howto perform PSFCH transmission.

Also, for example, when the UE performs a plurality of PSFCHtransmissions, since one PSFCH transmit power value is configured as themaximum transmit power value of the UE, a case in which power is limitedmay occur. At this time, for example, according to a pre-configured rule(e.g., a rule for sequentially omitting PSFCH transmission of arelatively low priority until it leaves a case in which power islimited) and/or UE implementation, there may be a problem in that the UEneeds to finally transmit one PSFCH or a relatively small number ofPSFCHs.

Also, for example, when one channel transmission (e.g., CH_1) overlapswith a plurality of channel transmissions (e.g., CH_2, CH_3) in the timedomain, the priority between the channels may be “CH_3>CH_1>CH_2”, andthe transmission start time in the time domain may be performed in theorder of “CH_2, CH_1, CH_3” (e.g., CH_2 and CH_3 do not overlap in thetime domain (i.e., TDM)). In this case, after the UE omits CH_2, whichhas a lower priority than CH_1, according to the priority, since thetemporally following CH_3 has a higher priority than CH_1, a problem ofomitting CH_1 may occur.

Technical Solutions

In an embodiment, a method for a first device to perform wirelesscommunication is provided. The method may comprise receiving at leastone physical sidelink control channel (PSCCH), receiving at least onephysical sidelink shared channel (PSSCH) related to the at least onePSCCH, determining a resource related to at least one physical sidelinkfeedback channel (PSFCH) based on an index of a slot and an index of asubchannel related to at least one PSSCH, determining N PSFCHs fromamong the at least one PSFCH based on the sum of power required totransmit the at least one PSFCH being greater than the maximum transmitpower of the first device, wherein N is selected from the number ofPSFCH transmissions with high priority among the maximum number of PSFCHtransmissions, to the maximum number of the PSFCH transmissions,determining transmit power for N PSFCHs, and transmitting N PSFCHs basedon the transmit power. For example, N may be an integer of 1 or more.For example, the transmit power related to the PSFCH transmissions withhigh priority may be less than or equal to the maximum transmit power ofthe first device.

In an embodiment, a first device performing wireless communication isprovided. The first device may include one or more memories for storinginstructions, one or more transceivers, and one or more processorsconnecting the one or more memories and the one or more transceivers.The one or more processors may execute the instructions to receive atleast one physical sidelink control channel (PSCCH), receive at leastone physical sidelink shared channel (PSSCH) related to the at least onePSCCH, determine a resource related to at least one physical sidelinkfeedback channel (PSFCH) based on an index of a slot and an index of asubchannel related to at least one PSSCH, determine N PSFCHs from amongthe at least one PSFCH based on the sum of power required to transmitthe at least one PSFCH being greater than the maximum transmit power ofthe first device, wherein N is selected from the number of PSFCHtransmissions with high priority among the maximum number of PSFCHtransmissions, to the maximum number of the PSFCH transmissions,determine transmit power for N PSFCHs, and transmit N PSFCHs based onthe transmit power. For example, N may be an integer of 1 or more. Forexample, the transmit power related to the PSFCH transmissions with highpriority may be less than or equal to the maximum transmit power of thefirst device.

Effects of the Disclosure

The user equipment (UE) can efficiently perform SL communication.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a drawing for describing V2X communication based on NR,compared to V2X communication based on RAT used before NR.

FIG. 2 shows a structure of an NR system, based on an embodiment of thepresent disclosure.

FIG. 3 shows a radio protocol architecture, based on an embodiment ofthe present disclosure.

FIG. 4 shows a structure of a radio frame of an NR, based on anembodiment of the present disclosure.

FIG. 5 shows a structure of a slot of an NR frame, based on anembodiment of the present disclosure.

FIG. 6 shows an example of a BWP, based on an embodiment of the presentdisclosure.

FIG. 7 shows a UE performing V2X or SL communication, based on anembodiment of the present disclosure.

FIG. 8 shows a procedure of performing V2X or SL communication by a UEbased on a transmission mode, based on an embodiment of the presentdisclosure.

FIG. 9 shows three cast types, based on an embodiment of the presentdisclosure.

FIG. 10 shows a method in which a UE that has reserved transmissionresource(s) informs another UE of the transmission resource(s), based onan embodiment of the present disclosure.

FIG. 11 illustrates a procedure for a receiving UE to transmit N PSFCHsto a transmitting UE according to an embodiment of the presentdisclosure.

FIG. 12 illustrates a method for a UE to select N from at least onePSFCH according to an embodiment of the present disclosure.

FIG. 13 illustrates an example in which an SL channel overlaps with aplurality of channels according to an embodiment of the presentdisclosure.

FIG. 14 illustrates a method for a first device to transmit N PSFCHsaccording to an embodiment of the present disclosure.

FIG. 15 illustrates a method for a second device to receive N PSFCHsaccording to an embodiment of the present disclosure.

FIG. 16 shows a communication system 1, based on an embodiment of thepresent disclosure.

FIG. 17 shows wireless devices, based on an embodiment of the presentdisclosure.

FIG. 18 shows a signal process circuit for a transmission signal, basedon an embodiment of the present disclosure.

FIG. 19 shows another example of a wireless device, based on anembodiment of the present disclosure.

FIG. 20 shows a hand-held device, based on an embodiment of the presentdisclosure.

FIG. 21 shows a vehicle or an autonomous vehicle, based on an embodimentof the present disclosure.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

In the present specification, “A or B” may mean “only A”, “only B” or“both A and B.” In other words, in the present specification, “A or B”may be interpreted as “A and/or B”. For example, in the presentspecification, “A, B, or C” may mean “only A”, “only B”, “only C”, or“any combination of A, B, C”.

A slash (/) or comma used in the present specification may mean“and/or”. For example, “A/B” may mean “A and/or B”. Accordingly, “A/B”may mean “only A”, “only B”, or “both A and B”. For example, “A, B, C”may mean “A, B, or C”.

In the present specification, “at least one of A and B” may mean “onlyA”, “only B”, or “both A and B”. In addition, in the presentspecification, the expression “at least one of A or B” or “at least oneof A and/or B” may be interpreted as “at least one of A and B”.

In addition, in the present specification, “at least one of A, B, and C”may mean “only A”, “only B”, “only C”, or “any combination of A, B, andC”. In addition, “at least one of A, B, or C” or “at least one of A, B,and/or C” may mean “at least one of A, B, and C”.

In addition, a parenthesis used in the present specification may mean“for example”. Specifically, when indicated as “control information(PDCCH)”, it may mean that “PDCCH” is proposed as an example of the“control information”. In other words, the “control information” of thepresent specification is not limited to “PDCCH”, and “PDCCH” may beproposed as an example of the “control information”. In addition, whenindicated as “control information (i.e., PDCCH)”, it may also mean that“PDCCH” is proposed as an example of the “control information”.

A technical feature described individually in one figure in the presentspecification may be individually implemented, or may be simultaneouslyimplemented.

The technology described below may be used in various wirelesscommunication systems such as code division multiple access (CDMA),frequency division multiple access (FDMA), time division multiple access(TDMA), orthogonal frequency division multiple access (OFDMA), singlecarrier frequency division multiple access (SC-FDMA), and so on. TheCDMA may be implemented with a radio technology, such as universalterrestrial radio access (UTRA) or CDMA-2000. The TDMA may beimplemented with a radio technology, such as global system for mobilecommunications (GSM)/general packet ratio service (GPRS)/enhanced datarate for GSM evolution (EDGE). The OFDMA may be implemented with a radiotechnology, such as institute of electrical and electronics engineers(IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, evolved UTRA(E-UTRA), and so on. IEEE 802.16m is an evolved version of IEEE 802.16eand provides backward compatibility with a system based on the IEEE802.16e. The UTRA is part of a universal mobile telecommunication system(UMTS). 3rd generation partnership project (3GPP) long term evolution(LTE) is part of an evolved UMTS (E-UMTS) using the E-UTRA. The 3GPP LTEuses the OFDMA in a downlink and uses the SC-FDMA in an uplink.LTE-advanced (LTE-A) is an evolution of the LTE.

5G NR is a successive technology of LTE-A corresponding to a newClean-slate type mobile communication system having the characteristicsof high performance, low latency, high availability, and so on. 5G NRmay use resources of all spectrum available for usage including lowfrequency bands of less than 1 GHz, middle frequency bands ranging from1 GHz to 10 GHz, high frequency (millimeter waves) of 24 GHz or more,and so on.

For clarity in the description, the following description will mostlyfocus on LTE-A or 5G NR. However, technical features according to anembodiment of the present disclosure will not be limited only to this.

FIG. 2 shows a structure of an NR system, based on an embodiment of thepresent disclosure. The embodiment of FIG. 2 may be combined withvarious embodiments of the present disclosure.

Referring to FIG. 2, a next generation-radio access network (NG-RAN) mayinclude a BS 20 providing a UE 10 with a user plane and control planeprotocol termination. For example, the BS 20 may include a nextgeneration-Node B (gNB) and/or an evolved-NodeB (eNB). For example, theUE 10 may be fixed or mobile and may be referred to as other terms, suchas a mobile station (MS), a user terminal (UT), a subscriber station(SS), a mobile terminal (MT), wireless device, and so on. For example,the BS may be referred to as a fixed station which communicates with theUE 10 and may be referred to as other terms, such as a base transceiversystem (BTS), an access point (AP), and so on.

The embodiment of FIG. 2 exemplifies a case where only the gNB isincluded. The BSs 20 may be connected to one another via Xn interface.The BS 20 may be connected to one another via 5th generation (5G) corenetwork (5GC) and NG interface. More specifically, the BSs 20 may beconnected to an access and mobility management function (AMF) 30 viaNG-C interface, and may be connected to a user plane function (UPF) 30via NG-U interface.

Layers of a radio interface protocol between the UE and the network canbe classified into a first layer (layer 1, L1), a second layer (layer 2,L2), and a third layer (layer 3, L3) based on the lower three layers ofthe open system interconnection (OSI) model that is well-known in thecommunication system. Among them, a physical (PHY) layer belonging tothe first layer provides an information transfer service by using aphysical channel, and a radio resource control (RRC) layer belonging tothe third layer serves to control a radio resource between the UE andthe network. For this, the RRC layer exchanges an RRC message betweenthe UE and the BS.

FIG. 3 shows a radio protocol architecture, based on an embodiment ofthe present disclosure. The embodiment of FIG. 3 may be combined withvarious embodiments of the present disclosure. Specifically, (a) of FIG.3 shows a radio protocol stack of a user plane for Uu communication, and(b) of FIG. 3 shows a radio protocol stack of a control plane for Uucommunication. (c) of FIG. 3 shows a radio protocol stack of a userplane for SL communication, and (d) of FIG. 3 shows a radio protocolstack of a control plane for SL communication.

Referring to FIG. 3, a physical layer provides an upper layer with aninformation transfer service through a physical channel. The physicallayer is connected to a medium access control (MAC) layer which is anupper layer of the physical layer through a transport channel. Data istransferred between the MAC layer and the physical layer through thetransport channel. The transport channel is classified according to howand with what characteristics data is transmitted through a radiointerface.

Between different physical layers, i.e., a physical layer of atransmitter and a physical layer of a receiver, data are transferredthrough the physical channel. The physical channel is modulated using anorthogonal frequency division multiplexing (OFDM) scheme, and utilizestime and frequency as a radio resource.

The MAC layer provides services to a radio link control (RLC) layer,which is a higher layer of the MAC layer, via a logical channel. The MAClayer provides a function of mapping multiple logical channels tomultiple transport channels. The MAC layer also provides a function oflogical channel multiplexing by mapping multiple logical channels to asingle transport channel. The MAC layer provides data transfer servicesover logical channels.

The RLC layer performs concatenation, segmentation, and reassembly ofRadio Link Control Service Data Unit (RLC SDU). In order to ensurediverse quality of service (QoS) required by a radio bearer (RB), theRLC layer provides three types of operation modes, i.e., a transparentmode (TM), an unacknowledged mode (UM), and an acknowledged mode (AM).An AM RLC provides error correction through an automatic repeat request(ARQ).

A radio resource control (RRC) layer is defined only in the controlplane. The RRC layer serves to control the logical channel, thetransport channel, and the physical channel in association withconfiguration, reconfiguration and release of RBs. The RB is a logicalpath provided by the first layer (i.e., the physical layer or the PHYlayer) and the second layer (i.e., a MAC layer, an RLC layer, a packetdata convergence protocol (PDCP) layer, and a service data adaptationprotocol (SDAP) layer) for data delivery between the UE and the network.

Functions of a packet data convergence protocol (PDCP) layer in the userplane include user data delivery, header compression, and ciphering.Functions of a PDCP layer in the control plane include control-planedata delivery and ciphering/integrity protection.

A service data adaptation protocol (SDAP) layer is defined only in auser plane. The SDAP layer performs mapping between a Quality of Service(QoS) flow and a data radio bearer (DRB) and QoS flow ID (QFI) markingin both DL and UL packets.

The configuration of the RB implies a process for specifying a radioprotocol layer and channel properties to provide a particular serviceand for determining respective detailed parameters and operations. TheRB can be classified into two types, i.e., a signaling RB (SRB) and adata RB (DRB). The SRB is used as a path for transmitting an RRC messagein the control plane. The DRB is used as a path for transmitting userdata in the user plane.

When an RRC connection is established between an RRC layer of the UE andan RRC layer of the E-UTRAN, the UE is in an RRC_CONNECTED state, and,otherwise, the UE may be in an RRC_IDLE state. In case of the NR, anRRC_INACTIVE state is additionally defined, and a UE being in theRRC_INACTIVE state may maintain its connection with a core networkwhereas its connection with the BS is released.

Data is transmitted from the network to the UE through a downlinktransport channel. Examples of the downlink transport channel include abroadcast channel (BCH) for transmitting system information and adownlink-shared channel (SCH) for transmitting user traffic or controlmessages. Traffic of downlink multicast or broadcast services or thecontrol messages can be transmitted on the downlink-SCH or an additionaldownlink multicast channel (MCH). Data is transmitted from the UE to thenetwork through an uplink transport channel. Examples of the uplinktransport channel include a random access channel (RACH) fortransmitting an initial control message and an uplink SCH fortransmitting user traffic or control messages.

Examples of logical channels belonging to a higher channel of thetransport channel and mapped onto the transport channels include abroadcast channel (BCCH), a paging control channel (PCCH), a commoncontrol channel (CCCH), a multicast control channel (MCCH), a multicasttraffic channel (MTCH), etc.

FIG. 4 shows a structure of a radio frame of an NR, based on anembodiment of the present disclosure. The embodiment of FIG. 4 may becombined with various embodiments of the present disclosure.

Referring to FIG. 4, in the NR, a radio frame may be used for performinguplink and downlink transmission. A radio frame has a length of 10 msand may be defined to be configured of two half-frames (HFs). Ahalf-frame may include five 1 ms subframes (SFs). A subframe (SF) may bedivided into one or more slots, and the number of slots within asubframe may be determined based on subcarrier spacing (SCS). Each slotmay include 12 or 14 OFDM(A) symbols according to a cyclic prefix (CP).

In case of using a normal CP, each slot may include 14 symbols. In caseof using an extended CP, each slot may include 12 symbols. Herein, asymbol may include an OFDM symbol (or CP-OFDM symbol) and a SingleCarrier-FDMA (SC-FDMA) symbol (or Discrete Fourier Transform-spread-OFDM(DFT-s-OFDM) symbol).

Table 1 shown below represents an example of a number of symbols perslot (N^(slot)symb), a number slots per frame (N^(frame,u)slot), and anumber of slots per subframe (N^(subframe,u)slot) based on an SCSconfiguration (u), in a case where a normal CP is used.

TABLE 1 SCS (15 * 2^(u)) N_(symb) ^(slot) N_(slot) ^(frame,u) N_(slot)^(subframe,u)  15 KHz (u = 0) 14 10 1  30 KHz (u = 1) 14 20 2  60 KHz (u= 2) 14 40 4 120 KHz (u = 3) 14 80 8 240 KHz (u = 4) 14 160  16 

Table 2 shows an example of a number of symbols per slot, a number ofslots per frame, and a number of slots per subframe based on the SCS, ina case where an extended CP is used.

TABLE 2 SCS (15 * 2^(u)) N_(symb) ^(slot) N_(slot) ^(frame,u) N_(slot)^(subframe,u) 60 KHz (u = 2) 12 40 4

In an NR system, OFDM(A) numerologies (e.g., SCS, CP length, and so on)between multiple cells being integrate to one UE may be differentlyconfigured. Accordingly, a (absolute time) duration (or section) of atime resource (e.g., subframe, slot or TTI) (collectively referred to asa time unit (TU) for simplicity) being configured of the same number ofsymbols may be differently configured in the integrated cells.

In the NR, multiple numerologies or SCSs for supporting diverse 5Gservices may be supported. For example, in case an SCS is 15 kHz, a widearea of the conventional cellular bands may be supported, and, in casean SCS is 30 kHz/60 kHz a dense-urban, lower latency, wider carrierbandwidth may be supported. In case the SCS is 60 kHz or higher, abandwidth that is greater than 24.25 GHz may be used in order toovercome phase noise.

An NR frequency band may be defined as two different types of frequencyranges. The two different types of frequency ranges may be FR1 and FR2.The values of the frequency ranges may be changed (or varied), and, forexample, the two different types of frequency ranges may be as shownbelow in Table 3. Among the frequency ranges that are used in an NRsystem, FR1 may mean a “sub 6 GHz range”, and FR2 may mean an “above 6GHz range” and may also be referred to as a millimeter wave (mmW).

TABLE 3 Frequency Range Corresponding Subcarrier designation frequencyrange Spacing (SCS) FR1  450 MHz-6000 MHz 15, 30, 60 kHz FR2 24250MHz-52600 MHz 60, 120, 240 kHz

As described above, the values of the frequency ranges in the NR systemmay be changed (or varied). For example, as shown below in Table 4, FR1may include a band within a range of 410 MHz to 7125 MHz. Morespecifically, FR1 may include a frequency band of 6 GHz (or 5850, 5900,5925 MHz, and so on) and higher. For example, a frequency band of 6 GHz(or 5850, 5900, 5925 MHz, and so on) and higher being included in FR1mat include an unlicensed band. The unlicensed band may be used fordiverse purposes, e.g., the unlicensed band for vehicle-specificcommunication (e.g., automated driving).

TABLE 4 Frequency Range Corresponding Subcarrier designation frequencyrange Spacing (SCS) FR1  410 MHz-7125 MHz 15, 30, 60 kHz FR2 24250MHz-52600 MHz 60, 120, 240 kHz

FIG. 5 shows a structure of a slot of an NR frame, based on anembodiment of the present disclosure. The embodiment of FIG. 5 may becombined with various embodiments of the present disclosure.

Referring to FIG. 5, a slot includes a plurality of symbols in a timedomain. For example, in case of a normal CP, one slot may include 14symbols. However, in case of an extended CP, one slot may include 12symbols. Alternatively, in case of a normal CP, one slot may include 7symbols. However, in case of an extended CP, one slot may include 6symbols.

A carrier includes a plurality of subcarriers in a frequency domain. AResource Block (RB) may be defined as a plurality of consecutivesubcarriers (e.g., 12 subcarriers) in the frequency domain. A BandwidthPart (BWP) may be defined as a plurality of consecutive (Physical)Resource Blocks ((P)RBs) in the frequency domain, and the BWP maycorrespond to one numerology (e.g., SCS, CP length, and so on). Acarrier may include a maximum of N number BWPs (e.g., 5 BWPs). Datacommunication may be performed via an activated BWP. Each element may bereferred to as a Resource Element (RE) within a resource grid and onecomplex symbol may be mapped to each element.

Hereinafter, a bandwidth part (BWP) and a carrier will be described.

The BWP may be a set of consecutive physical resource blocks (PRBs) in agiven numerology. The PRB may be selected from consecutive sub-sets ofcommon resource blocks (CRBs) for the given numerology on a givencarrier

For example, the BWP may be at least any one of an active BWP, aninitial BWP, and/or a default BWP. For example, the UE may not monitordownlink radio link quality in a DL BWP other than an active DL BWP on aprimary cell (PCell). For example, the UE may not receive PDCCH,physical downlink shared channel (PDSCH), or channel stateinformation—reference signal (CSI-RS) (excluding RRM) outside the activeDL BWP. For example, the UE may not trigger a channel state information(CSI) report for the inactive DL BWP. For example, the UE may nottransmit physical uplink control channel (PUCCH) or physical uplinkshared channel (PUSCH) outside an active UL BWP. For example, in adownlink case, the initial BWP may be given as a consecutive RB set fora remaining minimum system information (RMSI) control resource set(CORESET) (configured by physical broadcast channel (PBCH)). Forexample, in an uplink case, the initial BWP may be given by systeminformation block (SIB) for a random access procedure. For example, thedefault BWP may be configured by a higher layer. For example, an initialvalue of the default BWP may be an initial DL BWP. For energy saving, ifthe UE fails to detect downlink control information (DCI) during aspecific period, the UE may switch the active BWP of the UE to thedefault BWP.

Meanwhile, the BWP may be defined for SL. The same SL BWP may be used intransmission and reception. For example, a transmitting UE may transmitan SL channel or an SL signal on a specific BWP, and a receiving UE mayreceive the SL channel or the SL signal on the specific BWP. In alicensed carrier, the SL BWP may be defined separately from a Uu BWP,and the SL BWP may have configuration signaling separate from the UuBWP. For example, the UE may receive a configuration for the SL BWP fromthe BS/network. For example, the UE may receive a configuration for theUu BWP from the BS/network. The SL BWP may be (pre-)configured in acarrier with respect to an out-of-coverage NR V2X UE and an RRC_IDLE UE.For the UE in the RRC_CONNECTED mode, at least one SL BWP may beactivated in the carrier.

FIG. 6 shows an example of a BWP, based on an embodiment of the presentdisclosure. The embodiment of FIG. 6 may be combined with variousembodiments of the present disclosure. It is assumed in the embodimentof FIG. 6 that the number of BWPs is 3.

Referring to FIG. 6, a common resource block (CRB) may be a carrierresource block numbered from one end of a carrier band to the other endthereof. In addition, the PRB may be a resource block numbered withineach BWP. A point A may indicate a common reference point for a resourceblock grid.

The BWP may be configured by a point A, an offset N^(start)BWP from thepoint A, and a bandwidth N^(size)BWP. For example, the point A may be anexternal reference point of a PRB of a carrier in which a subcarrier 0of all numerologies (e.g., all numerologies supported by a network onthat carrier) is aligned. For example, the offset may be a PRB intervalbetween a lowest subcarrier and the point A in a given numerology. Forexample, the bandwidth may be the number of PRBs in the givennumerology.

Hereinafter, V2X or SL communication will be described.

A sidelink synchronization signal (SLSS) may include a primary sidelinksynchronization signal (PSSS) and a secondary sidelink synchronizationsignal (SSSS), as an SL-specific sequence. The PSSS may be referred toas a sidelink primary synchronization signal (S-PSS), and the SSSS maybe referred to as a sidelink secondary synchronization signal (S-SSS).For example, length-127 M-sequences may be used for the S-PSS, andlength-127 gold sequences may be used for the S-SSS. For example, a UEmay use the S-PSS for initial signal detection and for synchronizationacquisition. For example, the UE may use the S-PSS and the S-SSS foracquisition of detailed synchronization and for detection of asynchronization signal ID.

A physical sidelink broadcast channel (PSBCH) may be a (broadcast)channel for transmitting default (system) information which must befirst known by the UE before SL signal transmission/reception. Forexample, the default information may be information related to SLSS, aduplex mode (DM), a time division duplex (TDD) uplink/downlink (UL/DL)configuration, information related to a resource pool, a type of anapplication related to the SLSS, a subframe offset, broadcastinformation, or the like. For example, for evaluation of PSBCHperformance, in NR V2X, a payload size of the PSBCH may be 56 bitsincluding 24-bit cyclic redundancy check (CRC).

The S-PSS, the S-SSS, and the PSBCH may be included in a block format(e.g., SL synchronization signal (SS)/PSBCH block, hereinafter,sidelink-synchronization signal block (S-SSB)) supporting periodicaltransmission. The S-SSB may have the same numerology (i.e., SCS and CPlength) as a physical sidelink control channel (PSCCH)/physical sidelinkshared channel (PSSCH) in a carrier, and a transmission bandwidth mayexist within a (pre-)configured sidelink (SL) BWP. For example, theS-SSB may have a bandwidth of 11 resource blocks (RBs). For example, thePSBCH may exist across 11 RBs. In addition, a frequency position of theS-SSB may be (pre-)configured. Accordingly, the UE does not have toperform hypothesis detection at frequency to discover the S-SSB in thecarrier.

FIG. 7 shows a UE performing V2X or SL communication, based on anembodiment of the present disclosure. The embodiment of FIG. 7 may becombined with various embodiments of the present disclosure.

Referring to FIG. 7, in V2X or SL communication, the term ‘UE’ maygenerally imply a UE of a user. However, if a network equipment such asa BS transmits/receives a signal according to a communication schemebetween UEs, the BS may also be regarded as a sort of the UE. Forexample, a UE 1 may be a first apparatus 100, and a UE 2 may be a secondapparatus 200.

For example, the UE 1 may select a resource unit corresponding to aspecific resource in a resource pool which implies a set of series ofresources. In addition, the UE 1 may transmit an SL signal by using theresource unit. For example, a resource pool in which the UE 1 is capableof transmitting a signal may be configured to the UE 2 which is areceiving UE, and the signal of the UE 1 may be detected in the resourcepool.

Herein, if the UE 1 is within a connectivity range of the BS, the BS mayinform the UE 1 of the resource pool. Otherwise, if the UE 1 is out ofthe connectivity range of the BS, another UE may inform the UE 1 of theresource pool, or the UE 1 may use a pre-configured resource pool.

In general, the resource pool may be configured in unit of a pluralityof resources, and each UE may select a unit of one or a plurality ofresources to use it in SL signal transmission thereof.

Hereinafter, resource allocation in SL will be described.

FIG. 8 shows a procedure of performing V2X or SL communication by a UEbased on a transmission mode, based on an embodiment of the presentdisclosure. The embodiment of FIG. 8 may be combined with variousembodiments of the present disclosure. In various embodiments of thepresent disclosure, the transmission mode may be called a mode or aresource allocation mode. Hereinafter, for convenience of explanation,in LTE, the transmission mode may be called an LTE transmission mode. InNR, the transmission mode may be called an NR resource allocation mode.

For example, (a) of FIG. 8 shows a UE operation related to an LTEtransmission mode 1 or an LTE transmission mode 3. Alternatively, forexample, (a) of FIG. 8 shows a UE operation related to an NR resourceallocation mode 1. For example, the LTE transmission mode 1 may beapplied to general SL communication, and the LTE transmission mode 3 maybe applied to V2X communication.

For example, (b) of FIG. 8 shows a UE operation related to an LTEtransmission mode 2 or an LTE transmission mode 4. Alternatively, forexample, (b) of FIG. 8 shows a UE operation related to an NR resourceallocation mode 2.

Referring to (a) of FIG. 8, in the LTE transmission mode 1, the LTEtransmission mode 3, or the NR resource allocation mode 1, a BS mayschedule an SL resource to be used by the UE for SL transmission. Forexample, the BS may perform resource scheduling to a UE 1 through aPDCCH (e.g., downlink control information (DCI)) or RRC signaling (e.g.,Configured Grant Type 1 or Configured Grant Type 2), and the UE 1 mayperform V2X or SL communication with respect to a UE 2 according to theresource scheduling. For example, the UE 1 may transmit a sidelinkcontrol information (SCI) to the UE 2 through a physical sidelinkcontrol channel (PSCCH), and thereafter transmit data based on the SCIto the UE 2 through a physical sidelink shared channel (PSSCH).

Referring to (b) of FIG. 8, in the LTE transmission mode 2, the LTEtransmission mode 4, or the NR resource allocation mode 2, the UE maydetermine an SL transmission resource within an SL resource configuredby a BS/network or a pre-configured SL resource. For example, theconfigured SL resource or the pre-configured SL resource may be aresource pool. For example, the UE may autonomously select or schedule aresource for SL transmission. For example, the UE may perform SLcommunication by autonomously selecting a resource within a configuredresource pool. For example, the UE may autonomously select a resourcewithin a selective window by performing a sensing and resource(re)selection procedure. For example, the sensing may be performed inunit of subchannels. In addition, the UE 1 which has autonomouslyselected the resource within the resource pool may transmit the SCI tothe UE 2 through a PSCCH, and thereafter may transmit data based on theSCI to the UE 2 through a PSSCH.

FIG. 9 shows three cast types, based on an embodiment of the presentdisclosure. The embodiment of FIG. 9 may be combined with variousembodiments of the present disclosure. Specifically, (a) of FIG. 9 showsbroadcast-type SL communication, (b) of FIG. 9 shows unicast type-SLcommunication, and (c) of FIG. 9 shows groupcast-type SL communication.In case of the unicast-type SL communication, a UE may performone-to-one communication with respect to another UE. In case of thegroupcast-type SL transmission, the UE may perform SL communication withrespect to one or more UEs in a group to which the UE belongs. Invarious embodiments of the present disclosure, SL groupcastcommunication may be replaced with SL multicast communication, SLone-to-many communication, or the like.

Meanwhile, in the present disclosure, for example, a transmitting UE (TXUE) may be a UE which transmits data to a (target) receiving UE (RX UE).For example, the TX UE may be a UE which performs PSCCH transmissionand/or PSSCH transmission. Additionally/alternatively, for example, theTX UE may be a UE which transmits SL CSI-RS(s) and/or a SL CSI reportrequest indicator to the (target) RX UE. Additionally/alternatively, forexample, the TX UE may be a UE which transmits a (control) channel(e.g., PSCCH, PSSCH, etc.) and/or reference signal(s) on the (control)channel (e.g., DM-RS, CSI-RS, etc.), to be used for a SL radio linkmonitoring (RLM) operation and/or a SL radio link failure (RLF)operation of the (target) RX UE.

Meanwhile, in the present disclosure, for example, a receiving UE (RXUE) may be a UE which transmits SL HARQ feedback to a transmitting UE(TX UE) based on whether decoding of data received from the TX UE issuccessful and/or whether detection/decoding of a PSCCH (related toPSSCH scheduling) transmitted by the TX UE is successful.Additionally/alternatively, for example, the RX UE may be a UE whichperforms SL CSI transmission to the TX UE based on SL CSI-RS(s) and/or aSL CSI report request indicator received from the TX UE.Additionally/alternatively, for example, the RX UE is a UE whichtransmits a SL (L1) reference signal received power (RSRP) measurementvalue, to the TX UE, measured based on (pre-defined) reference signal(s)and/or a SL (L1) RSRP report request indicator received from the TX UE.Additionally/alternatively, for example, the RX UE may be a UE whichtransmits data of the RX UE to the TX UE. Additionally/alternatively,for example, the RX UE may be a UE which performs a SL RLM operationand/or a SL RLF operation based on a (pre-configured) (control) channeland/or reference signal(s) on the (control) channel received from the TXUE.

Meanwhile, in the present disclosure, for example, in case the RX UEtransmits SL HARQ feedback information for a PSSCH and/or a PSCCHreceived from the TX UE, the following options or some of the followingoptions may be considered. Herein, for example, the following options orsome of the following options may be limitedly applied only if the RX UEsuccessfully decodes/detects a PSCCH scheduling a PSSCH.

(1) groupcast option 1: no acknowledgement (NACK) information may betransmitted to the TX UE only if the RX UE fails to decode/receive thePSSCH received from the TX UE.

(2) groupcast option 2: If the RX UE succeeds in decoding/receiving thePSSCH received from the TX UE, ACK information may be transmitted to theTX UE, and if the RX UE fails to decode/receive the PSSCH, NACKinformation may be transmitted to the TX UE.

Meanwhile, in the present disclosure, for example, the TX UE maytransmit the following information or some of the following informationto the RX UE through SCI(s). Herein, for example, the TX UE may transmitsome or all of the following information to the RX UE through a firstSCI and/or a second SCI.

-   -   PSSCH (and/or PSCCH) related resource allocation information        (e.g., the location/number of time/frequency resources, resource        reservation information (e.g., period))    -   SL CSI report request indicator or SL (L1) reference signal        received power (RSRP) (and/or SL (L1) reference signal received        quality (RSRQ) and/or SL (L1) reference signal strength        indicator (RS SI)) report request indicator    -   SL CSI transmission indicator (or SL (L1) RSRP (and/or SL (L1)        RSRQ and/or SL (L1) RSSI) information transmission indicator)        (on a PSSCH)    -   Modulation and Coding Scheme (MCS) information    -   TX power information    -   L1 destination ID information and/or L1 source ID information    -   SL HARQ process ID information    -   New Data Indicator (NDI) information    -   Redundancy Version (RV) information    -   (Transmission traffic/packet related) QoS information (e.g.,        priority information)    -   SL CSI-RS transmission indicator or information on the number of        antenna ports for (transmitting) SL CSI-RS    -   TX UE location information or location (or distance range)        information of the target RX UE (for which SL HARQ feedback is        requested)    -   Reference signal (e.g., DM-RS, etc.) information related to        decoding (and/or channel estimation) of data transmitted through        a PSSCH. For example, information related to a pattern of        (time-frequency) mapping resources of DM-RS(s), RANK        information, antenna port index information, information on the        number of antenna ports, etc.

Meanwhile, in the present disclosure, for example, since the TX UE maytransmit a SCI, a first SCI and/or a second SCI to the RX UE through aPSCCH, the PSCCH may be replaced/substituted with the SCI and/or thefirst SCI and/or the second SCI. Additionally/alternatively, the SCI maybe replaced/substituted with the PSCCH and/or the first SCI and/or thesecond SCI. Additionally/alternatively, for example, since the TX UE maytransmit a second SCI to the RX UE through a PSSCH, the PSSCH may bereplaced/substituted with the second SCI.

Meanwhile, in the present disclosure, for example, if SCI configurationfields are divided into two groups in consideration of a (relatively)high SCI payload size, the first SCI including a first SCI configurationfield group may be referred to as a 1^(st) SCI, and the second SCIincluding a second SCI configuration field group may be referred to as a2^(nd) SCI. Also, for example, the 1^(st) SCI may be transmitted to thereceiving UE through a PSCCH. Also, for example, the 2^(nd) SCI may betransmitted to the receiving UE through a (independent) PSCCH or may bepiggybacked and transmitted together with data through a PSSCH.

Meanwhile, in the present disclosure, for example, the term“configure/configured” or the term “define/defined” may refer to(pre)configuration from a base station or a network (through pre-definedsignaling (e.g., SIB, MAC, RRC, etc.)) (for each resource pool).

Meanwhile, in the present disclosure, for example, since an RLF may bedetermined based on out-of-synch (OOS) indicator(s) or in-synch (IS)indicator(s), the RLF may be replaced/substituted with out-of-synch(OOS) indicator(s) or in-synch (IS) indicator(s).

Meanwhile, in the present disclosure, for example, an RB may bereplaced/substituted with a subcarrier. Also, in the present disclosure,for example, a packet or a traffic may be replaced/substituted with a TBor a MAC PDU based on a transmission layer.

Meanwhile, in the present disclosure, a CBG may be replaced/substitutedwith a TB.

Meanwhile, in the present disclosure, for example, a source ID may bereplaced/substituted with a destination ID.

Meanwhile, in the present disclosure, for example, an L1 ID may bereplaced/substituted with an L2 ID. For example, the L1 ID may be an L1source ID or an L1 destination ID. For example, the L2 ID may be an L2source ID or an L2 destination ID.

Meanwhile, in the present disclosure, for example, an operation of thetransmitting UE to reserve/select/determine retransmission resource(s)may include: an operation of the transmitting UE toreserve/select/determine potential retransmission resource(s) for whichactual use will be determined based on SL HARQ feedback informationreceived from the receiving UE.

Meanwhile, in the present disclosure, a sub-selection window may bereplaced/substituted with a selection window and/or the pre-configurednumber of resource sets within the selection window, or vice versa.

Meanwhile, in the present disclosure, SL MODE 1 may refer to a resourceallocation method or a communication method in which a base stationdirectly schedules SL transmission resource(s) for a TX UE throughpre-defined signaling (e.g., DCI or RRC message). For example, SL MODE 2may refer to a resource allocation method or a communication method inwhich a UE independently selects SL transmission resource(s) in aresource pool pre-configured or configured from a base station or anetwork. For example, a UE performing SL communication based on SL MODE1 may be referred to as a MODE 1 UE or MODE 1 TX UE, and a UE performingSL communication based on SL MODE 2 may be referred to as a MODE 2 UE orMODE 2 TX UE.

Meanwhile, in the present disclosure, for example, a dynamic grant (DG)may be replaced/substituted with a configured grant (CG) and/or asemi-persistent scheduling (SPS) grant, or vice versa. For example, theDG may be replaced/substituted with a combination of the CG and the SPSgrant, or vice versa. For example, the CG may include at least one of aconfigured grant (CG) type 1 and/or a configured grant (CG) type 2. Forexample, in the CG type 1, a grant may be provided by RRC signaling andmay be stored as a configured grant. For example, in the CG type 2, agrant may be provided by a PDCCH, and may be stored or deleted as aconfigured grant based on L1 signaling indicating activation ordeactivation of the grant.

Meanwhile, in the present disclosure, a channel may bereplaced/substituted with a signal, or vice versa. For example,transmission/reception of a channel may include transmission/receptionof a signal. For example, transmission/reception of a signal may includetransmission/reception of a channel. In addition, for example, cast maybe replaced/substituted with at least one of unicast, groupcast, and/orbroadcast, or vice versa. For example, a cast type may bereplaced/substituted with at least one of unicast, groupcast, and/orbroadcast, or vice versa.

Meanwhile, in the present disclosure, a resource may bereplaced/substituted with a slot or a symbol, or vice versa. Forexample, the resource may include a slot and/or a symbol.

Meanwhile, in the present disclosure, a priority may bereplaced/substituted with at least one of logical channel prioritization(LCP), latency, reliability, minimum required communication range, proseper-packet priority (PPPP), sidelink radio bearer (SLRB), QoS profile,QoS parameter and/or requirement, or vice versa.

Meanwhile, in various embodiments of the present disclosure, thereservation resource and/or the selection resource may bereplaced/substituted with a sidelink grant (SL GRANT).

Meanwhile, in various embodiments of the present disclosure, latency maybe replaced/substituted with a packet delay budget (PDB).

Meanwhile, in various embodiments of the present disclosure, a messagefor triggering a report on sidelink channel state information/sidelinkchannel quality information (hereinafter, SL_CSI information) may bereplaced/substituted with a sidelink channel state information referencesignal (CSI-RS) reception.

Meanwhile, in the present disclosure, blind retransmission may referthat the TX UE performs retransmission without receiving SL HARQfeedback information from the RX UE. For example, SL HARQ feedback-basedretransmission may refer that the TX UE determines whether to performretransmission based on SL HARQ feedback information received from theRX UE. For example, if the TX UE receives NACK and/or DTX informationfrom the RX UE, the TX UE may perform retransmission to the RX UE.

Meanwhile, in the present disclosure, for example, for convenience ofdescription, a (physical) channel used when a RX UE transmits at leastone of the following information to a TX UE may be referred to as aPSFCH.

-   -   SL HARQ feedback, SL CSI, SL (L1) RSRP

Meanwhile, in the present disclosure, a Uu channel may include a ULchannel and/or a DL channel. For example, the UL channel may include aPUSCH, a PUCCH, a sounding reference Signal (SRS), etc. For example, theDL channel may include a PDCCH, a PDSCH, a PSS/SSS, etc. For example, aSL channel may include a PSCCH, a PSSCH, a PSFCH, a PSBCH, a PSSS/SSSS,etc.

Meanwhile, in the present disclosure, sidelink information may includeat least one of a sidelink message, a sidelink packet, a sidelinkservice, sidelink data, sidelink control information, and/or a sidelinktransport block (TB). For example, sidelink information may betransmitted through a PSSCH and/or a PSCCH.

Meanwhile, in NR V2X communication or NR sidelink communication, atransmitting UE may reserve/select one or more transmission resourcesfor sidelink transmission (e.g., initial transmission and/orretransmission), and the transmitting UE may transmit information on thelocation of the one or more transmission resources to receiving UE(s).

Meanwhile, when performing sidelink communication, a method for atransmitting UE to reserve or pre-determine transmission resource(s) forreceiving UE(s) may be representatively as follows.

For example, the transmitting UE may perform a reservation oftransmission resource(s) based on a chain. Specifically, for example, ifthe transmitting UE reserves K transmission resources, the transmittingUE may transmit location information for less than K transmissionresources to receiving UE(s) through a SCI transmitted to the receivingUE(s) at any (or specific) transmission time or a time resource. Thatis, for example, the SCI may include location information for less thanthe K transmission resources. Alternatively, for example, if thetransmitting UE reserves K transmission resources related to a specificTB, the transmitting UE may transmit location information for less thanK transmission resources to receiving UE(s) through a SCI transmitted tothe receiving UE(s) at any (or specific) transmission time or a timeresource. That is, the SCI may include location information for lessthan the K transmission resources. In this case, for example, it ispossible to prevent performance degradation due to an excessive increasein payloads of the SCI, by signaling only the location information forless than K transmission resources to the receiving UE(s) through oneSCI transmitted at any (or specific) transmission time or the timeresource by the transmitting UE.

FIG. 10 shows a method in which a UE that has reserved transmissionresource(s) informs another UE of the transmission resource(s), based onan embodiment of the present disclosure. The embodiment of FIG. 10 maybe combined with various embodiments of the present disclosure.

Specifically, for example, (a) of FIG. 10 shows a method for performingby a transmitting UE chain-based resource reservation bytransmitting/signaling location information of (maximum) 2 transmissionresources to receiving UE(s) through one SCI, in the case of a value ofK=4. For example, (b) of FIG. 10 shows a method for performing by atransmitting UE chain-based resource reservation bytransmitting/signaling location information of (maximum) 3 transmissionresources to receiving UE(s) through one SCI, in the case of a value ofK=4. For example, referring to (a) and (b) of FIG. 10, the transmittingUE may transmit/signal only location information of the fourthtransmission-related resource to the receiving UE(s) through the fourth(or last) transmission-related PSCCH. For example, referring to (a) ofFIG. 10, the transmitting UE may transmit/signal to the receiving UE(s)not only location information of the fourth transmission-relatedresource but also location information of the third transmission-relatedresource additionally through the fourth (or last) transmission-relatedPSCCH. For example, referring to (b) of FIG. 10, the transmitting UE maytransmit/signal to the receiving UE(s) not only location information ofthe fourth transmission-related resource but also location informationof the second transmission-related resource and location information ofthe third transmission-related resource additionally through the fourth(or last) transmission-related PSCCH. In this case, for example, in (a)and (b) of FIG. 10, if the transmitting UE may transmit/signal to thereceiving UE(s) only location information of the fourthtransmission-related resource through the fourth (or last)transmission-related PSCCH, the transmitting UE may set or designate afield/bit of location information of unused or remaining transmissionresource(s) to a pre-configured value (e.g., 0). For example, in (a) and(b) of FIG. 10, if the transmitting UE may transmit/signal to thereceiving UE(s) only location information of the fourthtransmission-related resource through the fourth (or last)transmission-related PSCCH, the transmitting UE may be set or designatea field/bit of location information of unused or remaining transmissionresource(s) to a pre-configured status/bit value indicating/representingthe last transmission (among 4 transmissions).

Meanwhile, for example, the transmitting UE may perform a reservation oftransmission resource(s) based on a block. Specifically, for example, ifthe transmitting UE reserves K transmission resources, the transmittingUE may transmit location information for K transmission resources toreceiving UE(s) through a SCI transmitted to the receiving UE(s) at any(or specific) transmission time or a time resource. That is, the SCI mayinclude location information for K transmission resources. For example,if the transmitting UE reserves K transmission resources related to aspecific TB, the transmitting UE may transmit location information for Ktransmission resources to receiving UE(s) through a SCI transmitted tothe receiving UE(s) at any (or specific) transmission time or a timeresource. That is, the SCI may include location information for Ktransmission resources. For example, (c) of FIG. 10 shows a method forperforming by the transmitting UE block-based resource reservation, bysignaling location information of 4 transmission resources to receivingUE(s) through one SCI, in the case of a value of K=4.

Meanwhile, for example, since the base station cannot determine how manyresources the mode 1 transmitting UE requires for MAC PDU transmissionwith HARQ feedback disabled, mode 1 resource allocation/scheduling maybe inefficient.

According to various embodiments of the present disclosure, when themode 1 transmitting UE performs MAC PDU transmission with HARQ feedbackdisabled, if additional retransmission resources are not required, thetransmitting UE may report ACK information to the base station throughthe PUCCH resource. Here, for example, the PUCCH resource may be a PUCCHresource related to the previous mode 1 resource.

Meanwhile, for example, due to the decoding and/or reception performanceof the UE, since a size of the resource reservation period field on theSCI (hereinafter, RSV_BITNUM) is limited, a mapping relationship betweena reservation period value of the selectable candidate resourcesconfigured/allowed for the UE resource pool specifically and a bit valuefor a reservation period field of a resource may be ambiguous.

According to various embodiments of the present disclosure, the basestation/network may configure a candidate resource reservation periodvalue that can be used/selectable in the resource pool for the UE,within a range not exceeding 2∧{RSV_BITNUM}. In this case, for example,the candidate resource reservation period value configured for the UEmay be sequentially mapped from the first candidate resource reservationperiod to the ascending status of the decimal value of the RSV_BITNUMbit.

Meanwhile, for example, the transmitting UE may perform initialtransmission based on the mode 1 CG resource, and the transmitting UEmay report a NACK to the base station through a CG-related PUCCHresource. Thereafter, when the transmitting UE is scheduled withretransmission resources through DG DCI, it may be ambiguous when thetransmitting UE can expect retransmission resource scheduling related tothe corresponding sidelink HARQ process or when the transmitting UE canflush the associated buffer.

Or, for example, the transmitting UE may perform initial transmissionbased on the mode 1 CG resource, and the transmitting UE may report aNACK to the base station through a CG-related PUCCH resource.Thereafter, the transmitting UE may perform retransmission based on theDG DCI received from the base station. At this time, for example, whenthe transmitting UE reports a NACK to the base station through theDG-related PUCCH resource for scheduling the retransmission resource,and then is scheduled with additional retransmission resources throughthe DG DCI, it may be ambiguous when the transmitting UE can expectDG-based retransmission resource scheduling related to the correspondingsidelink HARQ process or when the transmitting UE can flush theassociated buffer.

According to various embodiments of the present disclosure, the DGDCI-based retransmission resource may be scheduled for the transmittingUE only up to a pre-configured time window from the CG resource of aspecific period in which the initial transmission was performed. Forexample, the transmitting UE may perform DG DCI-based retransmission fora related sidelink HARQ process up to a pre-configured time window fromthe CG resource of a specific period in which the initial transmissionwas performed. Here, for example, the related sidelink HARQ process maybe a sidelink HARQ process related to initial transmission performed bythe transmitting UE through a CG resource of a specific period.

Also, for example, after the pre-configured time window, it may beconfigured for the transmitting UE to flush the buffer related to theassociated sidelink HARQ process, or it may be configured to be allowedfor the transmitting UE to flush the buffer related to the associatedsidelink HARQ process. Here, for example, the associated sidelink HARQprocess may be a sidelink HARQ process related to initial transmissionperformed by the transmitting UE through a CG resource of a specificperiod. That is, for example, the transmitting UE may flush a bufferrelated to the associated sidelink HARQ process regardless of whether ornot NACK information is received from the receiving UE.

Meanwhile, for example, after the mode 1 transmitting UE receives ACKinformation from the receiving UE through the PSFCH, even though themode 1 transmitting UE reports the ACK information to the base stationthrough the PUCCH, the mode 1 transmitting UE may receive DG DCIscheduling retransmission resources related to the correspondingsidelink HARQ process from the base station. In this case, it may beambiguous whether the mode 1 transmitting UE should perform PSCCH/PSSCHtransmission or retransmission on the retransmission resource and whatinformation to report to the base station through the DG-related PUCCHresource.

According to various embodiments of the present disclosure, after themode 1 transmitting UE receives ACK information from the receiving UEthrough the PSFCH, even though the mode 1 transmitting UE reports theACK information to the base station through the PUCCH, based on the basestation misidentifying the ACK as the NACK, the mode 1 transmitting UEmay receive a DG DCI scheduling retransmission resources related to thecorresponding sidelink HARQ process from the base station. In this case,for example, the mode 1 transmitting UE may not perform PSCCH/PSSCHtransmission on the corresponding retransmission resource. For example,the mode 1 transmitting UE may also report ACK information to the basestation through the DG-related PUCCH resource.

Meanwhile, for example, a mode 2 transmitting UE may select atransmission resource based on sensing, and may signal reservationinformation related to the transmission resource through SCI. At thistime, when actual packet transmission is not performed due to causessuch as uplink/sidelink prioritization (UL/SL prioritization), LTE/NRsidelink prioritization, etc., if the packet transmission resource ofanother UE having a priority greater than or equal to a pre-configuredthreshold overlaps the corresponding transmission resource, it may beambiguous whether to perform preemption check and reselection oftransmission resource.

According to various embodiments of the present disclosure, when actualpacket transmission is not performed on the reserved resource signaledby the transmitting UE through SCI, based on the priority of packet/dataconsidered when performing sensing related to selection of thecorresponding reserved resource, the transmitting UE may perform apreemption check and resource reselection determination for a reservedresource for which actual packet transmission is not performed.Alternatively, for example, the preemption check and resourcereselection determination for the reserved resource signaled by the SCImay be performed when a packet (e.g., MAC PDU) to be transmitted throughthe corresponding reserved resource is available. That is, for example,the transmitting UE may perform the preemption check and resourcereselection determination for the reserved resource signaled by the SCIwhen a packet (e.g., MAC PDU) to be transmitted through thecorresponding reserved resource is available.

Meanwhile, according to an embodiment of the present disclosure, it maybe configured for the UE so that a Channel occupancy Ratio (CR)calculation related to sidelink communication is performed. For example,the UE may perform CR calculation related to sidelink communication.

According to an embodiment, the UE may select a transmission resourcebased on internal sensing. Thereafter, before the UE transmitsinformation related to the selected transmission resource to another UEthrough SCI, the UE may determine whether the selected transmissionresource overlaps all or part of the transmission resource of the otherUE. For example, when the selected transmission resource overlaps all orpart of the transmission resource of another UE, the UE may reselect thetransmission resource. For example, when the UE reselects a transmissionresource, it may be configured for the UE so that the previouslyselected transmission resource is not included in the CR calculation.For example, when the UE reselects the transmission resource, it may beconfigured for the UE so that the previously selected transmissionresource is included in the CR calculation.

Meanwhile, according to an embodiment of the present disclosure, a fieldrelated to period information of a reserved resource may be defined onthe SCI. For example, the SCI may include a field related to periodinformation of a reserved resource.

According to an embodiment, the size of a field related to periodinformation of a reserved resource included in the SCI may be configuredto X bits. The base station or the network may configure usable orselectable candidate period values in the resource pool to the UE. Forexample, the usable or selectable candidate period values in theresource pool may include values in a range not exceeding 2^(x) amongmore than 2^(x) candidate period values. For example, the base stationor the network may configure usable or selectable candidate periodvalues in the resource pool to the UE in a range that does not exceed2^(x) among more than 2^(x) candidate period values. Here, for example,the base station or the network may configure N (e.g., N<2^(x)+1) numberof the period (e.g., P₁, P₂, P₃, . . . , P_(N)) of reserved resources tothe UE. In this case, for example, from the first period P₁ , it may besequentially mapped to an ascending status of a decimal value of X bits(e.g., 0, 1, . . . , 2^(x)−1). For example, P₁ may be mapped to the 0state, P₂ be mapped to the 1 state, . . . , and P_(N) may be mapped tothe 2^(x)−1 state, respectively.

Meanwhile, according to an embodiment of the present disclosure, in thecase of operation related to mode 1 CG and/or DG, the UE may reportsidelink HARQ feedback information to the base station through apre-configured PUCCH. Thereafter, when the base station allocates anadditional retransmission resource to the UE through DG, according tovarious embodiments below, the UE may figure out the linkage between theCG index and/or the CG resource on which the initial transmission wasperformed and the retransmission resource allocated through the DG. Forexample, when the UE reports NACK information to the base stationthrough a pre-configured PUCCH, and the base station allocates anadditional retransmission resource to the UE through DG, according tovarious embodiments below, the UE may determine the DG retransmissionresource associated with the CG index and/or the CG resource, throughlinkage between the CG index and/or the CG resource on which the initialtransmission was performed and the retransmission resource allocatedthrough the DG.

According to an embodiment, on the DG DCI to which the retransmissionresource is allocated, a PUCCH resource index indicator field (PRI FD)may be defined. Here, for example, PUCCH resource indexing may beallocated for a periodically appearing CG resource or a PUCCH resourceconfigured according to a CG resource set, respectively. Specifically,for example, when the UE performs initial transmission based on a CGresource or CG resource set of a specific period, the UE may report aNACK to the base station through an associated PUCCH resource. In thiscase, the PRI_FD value on the DG DCI to which the retransmissionresource is allocated may be indicated by the index of the associatedPUCCH resource. For example, when the UE performs initial transmissionbased on a CG resource or CG resource set of a specific period, the UEmay report a NACK to the base station through a PUCCH resourceassociated with a CG resource or CG resource set of a specific period.For example, when the associated PUCCH resource index is X, the PRI_FDvalue on the DG DCI to which the retransmission resource is allocatedmay be expressed as X.

According to an embodiment, when the UE performs initial transmissionthrough a CG resource and an additional retransmission resource isallocated to the UE through the DG, the HARQ process ID field, not theCG index field, may be defined on the DCI related to the DG. Forexample, the DCI related to the DG may include a HARQ process ID fieldwithout including a CG index field indicating index information of a CGassociated with the DG. Here, for example, both the CG index field andthe HARQ process ID field may exist on the CG DCI, and HARQ process IDvalues may not overlap between different CGs. For example, the CG DCImay include a CG index field and a HARQ process ID field, and HARQprocess ID values may not overlap between different CGs. For example, inorder to remove ambiguity about the linkage between the CG resource andthe associated DG retransmission resource, it may be configured so thatthe HARQ process ID values do not overlap between different CGs.

Meanwhile, according to an embodiment of the present disclosure, whenthe UE performs a pre-emption operation, the UE may reselect atransmission resource according to the following various embodiments.For example, when the UE shares information related to a transmissionresource selected or reserved through SCI with another UE, when theresource related to transmission of a relatively higher priority packetoverlaps with the selected or reserved transmission resource, thepreemption operation may be operation of reselecting the selected orreserved resource or omitting transmission of the selected or reservedresource.

According to an embodiment, when packet transmission is not actuallyperformed on a specific transmission resource shared by the UE throughSCI, if the resource of a relatively high priority packet transmitted byanother UE and all or part of the specific transmission resourceoverlaps, the overlapping transmission resource may be reselected. Forexample, if there is no actual transmission packet, the referencepriority that the UE compares with the priority related to the packet ofanother UE may be considered the priority of the most recentlytransmitted packet on the selected or reserved resource shared throughSCI. Or, for example, when there is no actual transmission packet, thereference priority that the UE compares with the priority related to thepacket of another UE may be the priority of the packet considered whenthe UE performs sensing related to the selected or reserved resourceshared through SCI. Or, for example, when there is no actualtransmission packet, the reference priority that the UE compares withthe priority related to the packet of another UE may be considered thehighest priority of the service related to the selected or reservedresource shared by the UE through SCI. Alternatively, for example, whenthere is no actual transmission packet, the reference priority that theUE compares with the priority related to the packet of another UE may beconsidered the pre-configured priority.

According to an embodiment, when packet transmission is not actuallyperformed on a specific transmission resource shared by the UE throughSCI, if the resource of a relatively high priority packet transmitted byanother UE and all or part of the specific transmission resourceoverlaps, the UE performs a release operation on the overlappingtransmission resource, and the UE may reselect the actual transmissionresource as a packet is generated or arrived in the buffer. For example,when packet transmission is not actually performed on a specifictransmission resource shared by the UE through SCI, if the resource of arelatively high priority packet transmitted by another UE and all orpart of the specific transmission resource overlaps, the UE performs acancel operation on the existing sidelink grant, and the UE may reselectthe actual transmission resource as a packet is generated or arrived inthe buffer.

According to an embodiment, when a relatively low priority packettransmission has already occupied or reserved a resource through aninitial sensing operation, the preemption operation may be an operationin which transmission of a relatively high priority packet occupies orreserves a resource overlapping all or part of the occupied or reservedresource, thereby protecting the transmission of a relatively highpriority packet. That is, for example, the RSRP threshold associatedwith preemption may be configured differently from the sidelink RSRPthreshold associated with sensing. Here, for example, the RSRP thresholdassociated with preemption may include an RSRP threshold associated withpreemption triggering. Here, for example, the sidelink RSRP thresholdvalue related to sensing may be the final sidelink RSRP threshold valuerelated to the initial sensing or the sidelink RSRP threshold valueconfigured from the base station or the network.

Or, for example, when the UE performing the transmission of therelatively low priority packet performs initial sensing, the preemptionoperation may be an operation in which the UE fails to detect or sensetransmission of a relatively high priority packet, and then, the UEdetermines that the transmission resource of a relatively high prioritypacket and all or part of its transmission resource overlaps, therebyprotecting transmission of a relatively high priority packet. That is,for example, the RSRP threshold associated with preemption may beconfigured to be the same as the sidelink RSRP threshold associated withsensing. Here, for example, the RSRP threshold associated withpreemption may include an RSRP threshold associated with preemptiontriggering. Here, for example, the sidelink RSRP threshold value relatedto sensing may be the final sidelink RSRP threshold value related to theinitial sensing or the sidelink RSRP threshold value configured from thebase station or the network.

According to an embodiment, when the UE performs preemption-basedresource reselection, the UE may perform resource reselection by usingthe final sidelink RSRP threshold used during initial sensing. Forexample, the final sidelink RSRP threshold may be a value obtained byincreasing the sidelink RSRP threshold (e.g., increasing the sidelinkRSRP threshold by 3 DB) in order to secure the candidate number ofselectable transmission resources greater than or equal to apre-configured number or pre-configured ratio within the selectionwindow.

Or, for example, when the UE performs preemption-based resourcereselection, the UE may perform resource reselection by using a sidelinkRSRP threshold related to initial sensing pre-configured from a basestation or a network. For example, when the UE performs preemption-basedresource reselection, the UE may perform resource reselection a sidelinkRSRP threshold value related to initial sensing pre-configured from abase station or network rather than a final sidelink RSRP thresholdrelated to initial sensing.

Meanwhile, according to an embodiment of the present disclosure, whenthe number of RBs related to the sidelink BWP (BW_RBNUM) is greater thanthe number of RBs configurable as a frequency resource of the resourcepool (RP_RBNUM), in order to increase the resource usage rate, thefollowing various embodiments may be applied. Here, for example, theRP_RBNUM value may be the product of the number of RBs constituting asubchannel (SUB_RBNUM) and the number of subchannels in the resourcepool (SUB_NUM) (i.e., RP_RBNUM=SUB_RBNUM×SUB_NUM). Also, in the presentdisclosure, for convenience of description, a difference value betweenBW_RBNUM and RP_RBNUM may be referred to as X_VAL.

According to an embodiment, a subchannel of a low index may include allRBs corresponding to X_VAL. A subchannel of a high index may include allRBs corresponding to X_VAL. For example, a subchannel of apre-configured index may include all RBs corresponding to X_VAL.Alternatively, for example, in the ascending order of the index from thesubchannel of the lowest index, the subchannel may be configured toinclude the number of FLOOR (X_VAL/SUB_NUM) or CEILING (X_VAL/SUB_NUM)number of RBs. For example, in the descending order of the index fromthe subchannel of the highest index, the subchannel may be configured toinclude the number of FLOOR (X_VAL/SUB_NUM) or CEILING (X_VAL/SUB_NUM)number of RBs.

For example, when the above-described embodiment is applied, subchannelshaving different RB numbers may exist in the resource pool, and the TBSvalue may be configured to be derived based on the subchannel ofSUB_RBNUM. Also, for example, when the size of a subchannel used betweeninitial transmission and retransmission is different, the TBS value maybe configured to always be derived or assumed as an initialtransmission-related parameter (e.g., the number of RBs, MCS). Forexample, the TBS value may be determined by a combination of the MCS andthe number of RBs. For example, the TBS value may be configured toalways be derived or assumed based on the subchannel of SUB_RBNUM towhich the number of RBs is not added. Or, for example, when the size ofthe subchannel used between the initial transmission and theretransmission is different, the TBS value may be configured to bederived or assumed based on the subchannel having the smallest number ofRBs among the subchannels related to the initial transmission and theretransmission. Or, for example, when the size of the subchannel usedbetween the initial transmission and the retransmission is different,the TBS value may be configured to be derived or assumed based on thesubchannel having the largest number of RBs among the subchannelsrelated to the initial transmission and the retransmission. Or, forexample, when the size of a subchannel used between initial transmissionand retransmission is different, the TBS value may be configured to bederived or assumed based on the average number of RBs of subchannelsrelated to initial transmission and retransmission.

Meanwhile, according to an embodiment of the present disclosure, a PDBor latency budget value related to SL CSI reporting may be determined orselected through predefined signaling (e.g., PC5 RRC) between UEs. Forexample, T_VAL may include a PDB or latency budget related to SL CSIreporting. In this case, for example, since the base station of the mode1 UE performing the SL CSI reporting operation does not have informationon the T_VAL value, the base station may not be able to allocate a mode1 resource satisfying the T_VAL value. In order to solve this problem,for example, a mode 1 UE performing an SL CSI reporting operation mayreport T_VAL information related to a SL SCI report determined orselected between a pair of UE to the base station through predefinedsignaling (e.g., SL UE assistance information).

Meanwhile, according to an embodiment of the present disclosure, in thecase of SL CSI MAC CE, priority information signaled on SCI and priorityinformation considered by a higher layer (e.g., MAC, RLC, PDCP) may bedifferent. In this case, according to the following embodiment, PHYparameter adjustment based on congestion control (e.g., maximumallowable transmit power, allowed number of retransmissions, selectableMCS range, number of allowed RBs related to transmission, et.) may be beperformed or applied.

According to an embodiment, in the case of SL CSI MAC CE, PHY parameteradjustment based on congestion control may be applied based on priorityinformation considered by a higher layer (e.g., MAC, RLC, PDCP)differently from PSSCH/PSCCH. Alternatively, for example, PHY parameteradjustment based on congestion control may be applied based on priorityinformation signaled on SCI.

Meanwhile, according to an embodiment of the present disclosure, in thecase of the mode 1 CG operation, the UE may perform retransmission forthe initial transmission according to the following various embodiments.Here, for example, it may be configured to operate or use only one HARQprocess or HARQ process ID for each CG. For example, it may beconfigured to operate or use only one sidelink HARQ process or HARQprocess ID for each CG. For example, the number of HARQ processes orHARQ process IDs that can be operated or used for each CG and/or DG maybe configured from the base station/network. For example, the maximumnumber of sidelink HARQ processes or HARQ process IDs that can beoperated or used for each CG and/or DG may be configured from the basestation/network. For example, the HARQ process ID or the sidelink HARQprocess ID may be configured not to overlap between the CG and the DG.

According to an embodiment, when the UE performs initial transmission ona CG resource of a specific period, the UE may perform retransmissionoperation related to the initial transmission (e.g., the UE may reportSL HARQ feedback information to the base station through PUCCH, and maybe allocated retransmission resources from the base station through DG)until CG resources of the next cycle appears. Or, for example, when theUE performs initial transmission on a CG resource of a specific period,the UE may perform retransmission operation related to the initialtransmission until a pre-configured time window or until apre-configured timer is completed. Or, for example, when the UE performsinitial transmission on a CG resource of a specific period, the UE mayperform retransmission operation related to the initial transmission fora pre-configured number/interval (e.g., the number of DG transmissionsfor allocating retransmission resources, or the number of CG cycles).For example, when the above embodiment is applied, the maximum allowablenumber of retransmissions per priority per CG may be counted only up tothe section in which the retransmission operation is performed, and maybe initialized again. For example, when the above embodiment is applied,the maximum allowable number of retransmissions per CG and/or themaximum allowable number of retransmissions per priority may be countedonly up to a section in which a retransmission operation is performed,and may be initialized again. Here, for example, when the period inwhich the retransmission operation is performed has elapsed, thetransmitting UE may flush its buffer. For example, after a period inwhich the retransmission operation is performed, the transmitting UE mayflush its buffer regardless of receiving a NACK from the receiving UE.

According to an embodiment, in the case of mode 1 CG, the base stationmay allocate an additional retransmission resource to the transmittingUE through DG, and the transmitting UE receives ACK information from thereceiving UE, whereby the retransmission resource of the transmitting UEmay be released. For example, the released retransmission resource maynot appear/invalid in the next CG period. Also, for example, when thebase station allocates an additional retransmission resource to thetransmitting UE through DG with respect to a resource of a specific CGperiod, the retransmission resource may appear for a resource of asubsequent CG period, respectively. Or, for example, the retransmissionresource may appear limitedly only for the resource of the correspondingCG period.

According to an embodiment, if a plurality of sidelink HARQ processesare operated based on CG resources, when the transmitting UE reportssidelink HARQ feedback information to the base station through PUCCH,the transmitting UE may also report the associated sidelink HARQ processID information. For example, if a plurality of sidelink HARQ processesare operated based on CG resources, the transmitting UE may reportsidelink HARQ feedback information and sidelink HARQ process IDinformation to the base station through PUCCH. Here, for example, on theDG DCI for allocating retransmission resources, a CG index informationfield and a sidelink HARQ process ID information field may be defined.For example, the DG DCI for allocating retransmission resources mayinclude a field related to CG index information and a field related tosidelink HARQ process ID information. According to another embodiment,the retransmission resource allocated through the DG DCI may be sharedamong a plurality of sidelink HARQ processes. For example, inparticular, since the UE reports only 1 bit to the base station throughthe PUCCH, when SL HARQ feedback information related to a plurality ofsidelink HARQ processes is bundled, the retransmission resourceallocated through the DG DCI may be shared between the plurality ofsidelink HARQ processes. For example, when the above-describedembodiment is applied or when a plurality of sidelink HARQ processes areoperated based on CG resources, the retransmission resource allocatedthrough the DG DCI may be shared among a plurality of sidelink HARQprocesses for which a NACK is reported (e.g., it may be limited to asidelink HARQ process related to the same CG). For example, inparticular, since the UE reports only 1 bit to the base station throughthe PUCCH, it may be applied when SL HARQ feedback information relatedto a plurality of sidelink HARQ processes is bundled.

Meanwhile, according to an embodiment of the present disclosure, whenthe mode 1 transmitting UE reports ACK information received from thereceiving UE to the base station through the pre-configured PUCCHresource, due to the occurrence of an ACK-TO-NACK error, and if the basestation misinterprets the ACK information as NACK information andallocates a retransmission resource via DG to the transmitting UE, thefollowing embodiments may be applied.

According to an embodiment, the transmitting UE may report ACKinformation to the base station through the PUCCH resource indicated bythe DG DCI without actually performing retransmission through theretransmission resource allocated through the DG.

According to an embodiment, the transmitting UE may use theretransmission resource allocated through the DG for new TBtransmission. For example, the receiving UE may distinguish whether anew TB is transmitted or not based on the sidelink HARQ process IDinformation and the NDI information on the SCI.

According to an embodiment, when the transmitting UE is configured witha PUCCH-based sidelink HARQ feedback report, even if the transmitting UEreceives ACK information from the receiving UE through the PSFCH, thetransmitting UE may be configured not to flush its own buffer for apre-configured period/timer. Or, for example, if the transmitting UE isconfigured with a PUCCH-based sidelink HARQ feedback report, even if thetransmitting UE receives ACK information from the receiving UE throughthe PSFCH, the transmitting UE may be configured not to flush its ownbuffer until receiving a DG (for allocating retransmission resources)containing the same HARQ process ID and/or CG index information andtoggled NDI information. For example, even when unnecessaryretransmission resources are allocated to the transmitting UE through DGdue to an ACK-TO-NACK error, in order for the transmitting UE to performretransmission to the receiving UE, the transmitting UE may not flushits own buffer for a pre-configured period/timer. Or, the transmittingUE may not flush its own buffer until receiving a DG (for allocatingretransmission resources) containing the same HARQ process ID and/or CGindex information and toggled NDI information

Meanwhile, according to an embodiment of the present disclosure, whenthe transmitting UE reserves a plurality of retransmission resources fora potential retransmission operation, the transmitting UE may receiveACK information from the receiving UE. At this time, if the transmittingUE releases the remaining retransmission resources, the transmitting UEmay perform counting of the number of retransmissions per TB or countingof the number of retransmissions per priority according to the followingvarious embodiments.

According to an embodiment, the transmitting UE may assume that theretransmission operation is performed on the remaining transmissionretransmission resources, and the transmitting UE may perform countingof the number of retransmissions per TB or counting of the number ofretransmissions per priority considering the released remainingtransmission retransmission resources. Or, for example, the transmittingUE may not consider the released remaining retransmission resources incounting the number of retransmissions per TB or counting the number ofretransmissions per priority. For example, since the transmitting UE hasalready signaled that it has reserved the corresponding resource throughSCI to another UE, the transmitting UE may assume that theretransmission operation is performed on the remaining transmissionretransmission resources, and the transmitting UE may perform countingof the number of retransmissions per TB or counting of the number ofretransmissions per priority considering the released remainingtransmission retransmission resources.

According to another embodiment, when the transmitting UE fails toperform actual transmission or retransmission on a reserved or selectedresource for a specific TB due to a collision between uplinktransmission and/or sidelink transmission, etc., the transmitting UE mayreflect the failure to perform actual transmission or retransmission onthe reserved or selected resource in counting the number ofretransmissions per TB or counting the number of retransmissions perpriority. Or, for example, when the transmitting UE fails to performactual transmission or retransmission on a reserved or selected resourcefor a specific TB due to a collision between uplink transmission and/orsidelink transmission, etc., the transmitting UE may not reflect thefailure to perform actual transmission or retransmission on the reservedor selected resource in counting the number of retransmissions per TB orcounting the number of retransmissions per priority.

Meanwhile, according to an embodiment of the present disclosure, thetotal number of sidelink HARQ processes (e.g., K) that the UE canoperate may be more than the number of statuses that can be indicated bythe sidelink HARQ process ID field on the SCI. In this case, accordingto the following various embodiments, the UE may be configured tooperate the sidelink HARQ process.

According to an embodiment, when the UE is operating a plurality ofsessions, the maximum number of sidelink HARQ processes that can beused/allocated to one session may be limited to the number of statusesthat can be indicated by the sidelink HARQ process ID field on the SCI,or may be limited to a pre-configured maximum number value.

According to an embodiment, the index related to the entire sidelinkHARQ processes that the UE can operate may have a value from 0 to (K−1),but since the number of sidelink HARQ process indexes and/or sidelinkHARQ processes (e.g., indexes from 0 to 7 may be expressed) that can beexpressed by the sidelink HARQ process ID field (e.g., 3 bits) on theSCI is smaller than the index related to the entire sidelink HARQprocesses that the UE can operate, the value of the sidelink HARQprocess ID field on the SCI may be determined through the operation ofMOD (X, 8). Here, for example, X may mean an index from 0 to (K−1). Forexample, MOD (A, B) may be a function that derives the remainder ofdividing A by B.

According to an embodiment, the mode 1 UE may report, to the basestation, information on the total number of sidelink HARQ processes thatcan be operated and/or information on the size of a soft buffer relatedto its own sidelink communication as capability information. Here, forexample, the size of the HARQ process ID field on mode 1 DCI (e.g., DGor CG) may be determined or configured based on the capabilityinformation.

According to an embodiment, if mode 1 CG operation is performed, when itis configured for the UE to report PUCCH-based sidelink HARQ feedbackinformation (e.g., in particular, when only 1 bit is reported throughPUCCH), one sidelink HARQ process or sidelink HARQ process ID per CG maybe operated or used. For example, when mode 1 CG operation is performed,when it is not configured for the UE to report PUCCH-based sidelink HARQfeedback information (e.g., in particular, when only 1 bit is reportedthrough PUCCH), the number of sidelink HARQ processes or sidelink HARQprocess IDs per CG operated or used may be determined by the UEimplementation. That is, for example, the UE may independently determinewhether to operate or use a plurality of sidelink HARQ processes orsidelink HARQ process IDs for a specific CG. Alternatively, for example,the maximum number of allowed sidelink HARQ process per CG or themaximum number of allowed sidelink HARQ process IDs operated or used maybe per-configured.

Meanwhile, according to an embodiment of the present disclosure, whenthe UE performs CR evaluation, the base station or the network maysignal to the UE information on at least to what extent a future timeinterval and/or a past time interval will be included among apre-configured CR evaluation window. For example, when the UE performsCR evaluation, the base station or the network may signal the UEinformation on at least to what extent the future time interval relatedto the resource reserved by the UE and/or the past time interval relatedto the resource reserved by the UE will be included among thepre-configured CR evaluation window. Or, for example, when the UEperforms CR evaluation, the base station or the network may signal tothe UE information on how much of the future time interval and/or thepast time interval to be included among the pre-configured CR evaluationwindow as much as possible. For example, when the UE performs CRevaluation, the base station or the network may signal to the UEinformation on how much of the future time interval related to theresource reserved by the UE and/or the past time interval related to theresource reserved by the UE to be included among the pre-configured CRevaluation window as much as possible. Here, for example, the length ofthe time interval may be specifically or independently configured for atleast one of the service type, service priority, cast type (e.g.,unicast, groupcast, broadcast), message generation type (e.g., periodic,aperiodic) and QoS requirements (e.g., latency, reliability).

For example, the base station or the network may signal to the UEinformation on the minimum future time interval and/or the minimum pasttime interval among the pre-configured CR evaluation window.Alternatively, for example, the base station or the network may signalto the UE information on the maximum future time interval and/or themaximum past time interval among the pre-configured CR evaluationwindow.

Meanwhile, according to an embodiment of the present disclosure, whenthe UE reserves additional transmission resources or retransmissionresources, based on the last transmission resource signaled by theprevious SCI or the pre-configured X-th resource, the UE may constitutea selection window for selecting additional transmission resources orretransmission resources. Here, for example, the selection window mayhave a pre-configured size (e.g., a range within 31 slots or 32 slots).Here, for example, the UE may select additional transmission resourcesor retransmission resources from among the resources within theselection window after the time of the last transmission resourcesignaled by the previous SCI or the pre-configured X-th resource. Also,for example, the UE may select additional transmission resources oradditional retransmission resources within the selection window, exceptfor slots related to transmission resources previously signaled by SCI.

Meanwhile, according to an embodiment of the present disclosure, whenthe UE selects three transmission resources, the UE may preferentiallyrandomly select the first transmission resource from among thesensing-based selectable candidate resources within the selectionwindow. Thereafter, the UE may additionally select two transmissionresources within a pre-configured time window (e.g., 32 slots) based onthe selected first transmission resource. Here, for example, when the UEadditionally selects two transmission resources, from among theselectable candidate resources on the remaining slots within theselection window, except for the slot related to the selected firsttransmission resource, until both the selected first transmissionresource and the remaining two transmission resources can be includedwithin the pre-configured time window, the UE may repeat randomselection for two transmission resources. In addition, for example,based on the above rule, after the UE completes the selection of threetransmission resources, the UE may select an additional transmissionresource based on the second transmission resource or the last resourcesignaled by SCI or the pre-configured X-th transmission resource. Inthis case, the additionally selected transmission resource may belocated before the third transmission resource signaled by SCI. Forexample, in the case of a service requiring low latency, based on theabove rule, after the UE completes selection of three transmissionresources, the UE may select an additional transmission resource basedon the second transmission resource or the last resource signaled by SCIor the pre-configured X-th transmission resource. In this case, some ofthe additionally selected transmission resources may be located beforethe third transmission resource signaled by SCI.

Here, for example, in order to include a PSFCH resource or a PSFCH slotbetween the transmission resources (e.g., transmission resource A andtransmission resource B) to be selected by the UE, after the UE randomlyselects the transmission resource A, the UE may select the transmissionresource B from among resources after the pre-configured N slots or thepre-configured N symbols from the nearest PSFCH resource or PSFCH slotthat appears after the pre-configured M slots based on the time of thetransmission resource A. For example, the pre-configured M slots mayinclude a processing time for PSSCH/PSCCH reception and a preparationtime for PSFCH transmission. For example, the pre-configured N slots orthe pre-configured N symbols may include a processing time for PSFCHreception and a preparation time for PSSCH/PSCCH retransmission. Or, forexample, the UE may select a transmission resource A from amongresources before M slots from a PSFCH resource or the PSFCH slot, withina pre-configured time window (e.g., 32) based on the PSFCH resource orthe PSFCH slot. Thereafter, the UE may select a transmission resource Bfrom among resources after N slots or N symbols from a PSFCH resource ora PSFCH slot. Here, for example, the selected transmission resource A ortransmission resource B and the PSFCH resource or PSFCH slot may beincluded in a pre-configured time window (e.g., 32). For example, theselected transmission resource A and transmission resource B and thePSFCH resource or PSFCH slot may all be included in a pre-configuredtime window (e.g., 32).

Meanwhile, according to an embodiment of the present disclosure, whenthe mode 1 transmitting UE performs a specific TB transmission on asidelink transmission resource scheduled from the base station,according to a predefined rule, an operation related to the TBtransmission may be omitted. In this case, for example, the mode 1transmitting UE may report NACK information to the base station throughthe PUCCH resource, and may be allocated an additional retransmissionresource from the base station. Here, for example, according to abovethe rule, when uplink transmission and/or downlink reception andsidelink transmission #X overlap in the time domain, operations relatedto sidelink transmission #X may be omitted based on comparing thepriorities of associated logical channels. And/or, for example, whenuplink transmission and/or sidelink transmission #X and sidelinktransmission #Y on different carriers overlap in the time domain, andwhen transmit power is first allocated to uplink transmission and/orsidelink transmission #X based on comparing the priorities of theassociated logical channels, since there is no remaining transmit powerthat can be allocated for sidelink transmission #Y, the operationrelated to sidelink transmission #Y may be omitted. Here, for example,the rule may be applied when the UE normally performs TB-related initialtransmission and omits the retransmission operation, on the mode 1 SLtransmission resource. For example, the resource allocated to the UEthrough the PUCCH-based NACK information report may be considered toadditionally perform the omitted retransmission. For example, the rulemay be applied to packet transmission or service transmission of apriority higher than a pre-configured threshold value and/or a QoSrequirement (e.g., latency, reliability) tighter than a pre-configuredthreshold value, and/or mode 1 CG/DG-based packet transmission orservice transmission. For example, the rule may be applied when acongestion level (e.g., a CBR measurement value) of the resource pool islower than a pre-configured threshold value. For example, the rule maybe applied when a congestion level (e.g., a CBR measurement value) ofthe resource pool is higher than a pre-configured threshold value.

Meanwhile, according to an embodiment of the present disclosure, inorder to efficiently support a service having a minimum communicationrange requirement, a TX-RX distance-based feedback operation fortransmitting only NACK may be performed or configured. For example, inorder to efficiently support a service having a minimum communicationrange requirement, the UE may perform group cast option 1 based on thedistance between the transmitting UE and the receiving UE (e.g., NACK(no acknowledgment) information is transmitted to the transmitting UEonly when the receiving UE fails to decode/receive the PSSCH receivedfrom the transmitting UE). In such a case, for example, when thereceiving UE cannot know its location information and/or when theaccuracy of its location information is lower than a pre-configuredthreshold value, the receiving UE may not perform the PSFCH transmission(i.e., sidelink HARQ feedback information transmission) to thetransmitting UE. Here, for example, when the operation of the group castoption 1 is applied, according to the above rule, when the PSFCHtransmission is not performed, it may be considered that the receivingUE transmits ACK information to the transmitting UE.

Meanwhile, according to an embodiment of the present disclosure, when abase station signals a mode 1 grant to the transmitting UE, anassociated PUCCH resource may be allocated or scheduled for thetransmitting UE. Thereafter, when the transmitting UE performstransmission without requesting or receiving sidelink HARQ feedback fromthe receiving UE through the mode 1 transmission resource, if additionalretransmission resources are needed to satisfy service-relatedrequirements (e.g., latency, reliability), the transmitting UE mayreport NACK information to the base station through PUCCH. On the otherhand, for example, when additional retransmission resources are notrequired, the transmitting UE may report ACK information to the basestation through the PUCCH. Or, for example, the transmitting UE may notperform PUCCH transmission. For example, when the transmitting UEperforms blind retransmission through mode 1 transmission resources, thetransmitting UE may report NACK information to the base station throughPUCCH based on the additional retransmission resources being needed. Or,for example, when the transmitting UE performs blind retransmissionthrough the mode 1 transmission resource, the transmitting UE may reportACK information to the base station through PUCCH based on theadditional retransmission resources not being needed.

Meanwhile, according to an embodiment of the present disclosure, whenresource reselection is triggered at slot #N time, based on the sensingresult acquired within the interval from slot # (N−offset1) to slot #(N−SEN_WIN), the transmitting UE may select a transmission resourcewithin the selection window period from slot # (N+offset2) to slot #(N+offset3). For example, SEN_WIN may be a value greater than offset1.For example, offset3 may be a value greater than offset2. Here, forexample, SEN_WIN may be the length of the sensing window. In addition,the length of the sensing window may be pre-configured from the basestation/network. Also, for example, offset3 may be selected to a valueless than or equal to a Packet Delay Budget (PDB) of the transmissionpacket. That is, for example, offset3 may be less than or equal to aPacket Delay Budget (PDB) of the transmission packet. For example,according to the procedure described above, after the transmitting UEselects a transmission resource (e.g., slot # (N+offset2+K)) within theselection window, when the transmission resource of another UE overlapswith the transmission resource before signaling for the SCI related tothe transmission resource is performed, the transmitting UE may reselectthe previously selected transmission resource. Such an operation may bereferred to as a re-evaluation procedure. Here, for example, the sensingoperation related to the re-evaluation procedure may be configured to beperformed or triggered only from the above-described slot #N to the slot# (N+offset2+K−T1). Or, for example, the sensing operation related tothe re-evaluation procedure may be configured to be performed ortriggered only from the above-described slot # (N−offset1) to the slot #(N+offset2+K−T1). Alternatively, for example, the sensing operationrelated to the re-evaluation procedure may be configured to be performedor triggered only from the above-described slot # (N−SEN_WIN) to theslot # (N+offset2+K−T1). Or, for example, the sensing operation relatedto the re-evaluation procedure may be configured to be performed ortriggered only from the above-described slot # (N+offset2) to the slot #(N+offset2+K−T1). Here, for example, T1 may be a processing timerequired for resource reselection based on re-evaluation sensing.

Meanwhile, according to an embodiment of the present disclosure, aresource reservation period on SCI signaled by a transmitting UEbelonging to a different base station or network may be interpretedambiguously. Therefore, for example, the size of the field related tothe resource reservation period on the SCI may be defined (e.g., CEILING(log₂N)) based on the maximum number of configurable periods (e.g., N).Also, for example, ascending values of N periods may be mapped toascending order status of bit values related to each field. For example,the transmitting UE may determine (e.g., CEILING (log₂N)) the size ofthe field related to the resource reservation period on the SCI based onthe maximum number of configurable periods (e.g., N). Here, for example,when the above-described embodiment is applied, even if different basestations or networks configure differently the reservation period valueor the number of reservation periods of resources allowed for eachresource pool, the transmitting UE belonging to different base stationsor networks may determine the resource reservation period on SCI withoutambiguity.

Meanwhile, according to an embodiment of the present disclosure, a rulefor determining a resource related to PSFCH transmission between unicastand groupcast may be configured differently. Specifically, for example,in the case of groupcast, unlike unicast, the number of members in agroup (NUM_GP) may be used as a parameter for determining a PSFCHtransmission resource related to a received PSSCH/PSCCH. For example, inthe case of unicast, NUM_GP may be assumed to be 0. For example, in thecase of unicast, NUM_GP may be 0. For convenience of description below,for example, a unicast HARQ feedback scheme is referred to as UN_HARQ,and a groupcast HARQ feedback scheme is referred to as GP_HARQ,respectively. When the above-described embodiment is applied, forexample, if it is not indicated/distinguished which feedback schemeamong UN_HARQ and GP_HARQ is requested on SCI related to PSSCH,ambiguity may occur in the side of the receiving UE. For example, ifunicast/groupcast and/or UN_HARQ/GP_HARQ uses the same SCI format or2^(nd) SCI format, if it is not indicated/distinguished which feedbackscheme among UN_HARQ and GP_HARQ is requested on SCI related to PSSCH,ambiguity may occur in the side of the receiving UE. For example, if theL1 destination ID and/or the L1 source ID on the SCI related tounicast/groupcast and/or UN_HARQ/GP_HARQ are the same, if it is notindicated/distinguished which feedback scheme among UN_HARQ and GP_HARQis requested on SCI related to PSSCH, ambiguity may occur in the side ofthe receiving UE. For example, in order to solve such a problem, thereceiving UE may determine an applied sidelink HARQ feedback schemeaccording to various embodiments below.

According to an embodiment, when the receiving UE receives the SCIindicated by the L1 destination ID (e.g., LSB 16 bits of the L2destination ID) determined in the PC5 RRC connection established by thereceiving UE, the receiving UE may transmit sidelink HARQ feedback forthe PSSCH related to the SCI in the UN_HARQ or GP_HARQ scheme.

According to another embodiment, when the receiving UE receives the SCIindicated by the L1 destination ID determined in the PC5 RRC connectionestablished by the receiving UE, the receiving UE may additionally checkthe L1 source ID on the SCI. At this time, for example, if it matchesthe L1 source ID (e.g., LSB 8 bits of the L2 source ID) determined inthe PC5 RRC connection established by the receiving UE, the receiving UEmay transmit sidelink HARQ feedback for the PSSCH related to the SCIwith the UN_HARQ or GP_HARQ scheme. For example, other than the casesdescribed above, the receiving UE may transmit sidelink HARQ feedbackfor the PSSCH related to the SCI with a GP_HARQ or UN_HARQ scheme. Thatis, for example, when the L1 ID determined in the PC5 RRC connection andthe L1 ID on the SCI do not match, the receiving UE may transmitsidelink HARQ feedback for the PSSCH related to the SCI with the GP_HARQor UN_HARQ scheme. For example, if it matches the L1 source ID (e.g.,LSB 8 bits of the L2 source ID) determined in the PC5 RRC connectionestablished by the receiving UE, the receiving UE may transmit sidelinkHARQ feedback for the PSSCH related to the SCI with UN_HARQ scheme. Forexample, if it does not match with the L1 source ID (eg, LSB 8 bits ofthe L2 source ID) determined in the PC5 RRC connection established bythe receiving UE, the receiving UE may transmit sidelink HARQ feedbackfor the PSSCH related to the SCI with GP_HARQ scheme. For example, inthe above-described rule, one of the UN_HARQ scheme or the GP_HARQscheme may be selected according to whether the L1 ID determined or usedin the PC5 RRC connection and the L1 ID on the SCI are the same.

According to another embodiment, when the receiving UE does notestablish a PC5 RRC connection, the receiving UE may transmit sidelinkHARQ feedback for the PSSCH related to SCI with a UN_HARQ or GP_HARQscheme.

Meanwhile, according to an embodiment, in the case of a TX-RXdistance-based sidelink HARQ feedback operation (e.g., group cast option1), according to the following embodiment, a sidelink HARQ feedbackoperation without consideration of the TX-RX distance may be indicatedfor the UE. For example, in the case of a TX-RX distance-based sidelinkHARQ feedback operation (e.g., group cast option 1), according to thefollowing embodiment, disabling of the TX-RX distance-based sidelinkHARQ feedback operation may be indicated.

According to an embodiment, when the minimum communication range fieldand/or the zone ID field related to the transmitting UE defined on theSCI indicates a pre-configured specific status or value, a sidelink HARQfeedback operation without consideration of the TX-RX distance may betriggered for the UE. For example, when the minimum communication rangefield and/or the zone ID field related to the transmitting UE defined onthe SCI indicates a pre-configured specific status or value, the TX-RXdistance-based sidelink HARQ feedback operation may be disabled for theUE. For example, the SCI may be the 2^(nd) SCI. Specifically, forexample, when the minimum communication range field indicates apre-configured value of infinity, the receiving UE receiving the SCI maytransmit NACK information to the transmitting UE if PSSCH decoding failswithout considering the TX-RX distance. Or, for example, even if thereceiving UE fails to decode the PSSCH, the sidelink HARQ feedback(e.g., NACK) may not be transmitted to the transmitting UE. Or, forexample, when the minimum communication range field indicates apre-configured value of 0, the receiving UE receiving the SCI maytransmit NACK information to the transmitting UE if PSSCH decoding failswithout considering the TX-RX distance. Or, for example, even if thereceiving UE fails to decode the PSSCH, the sidelink HARQ feedback(e.g., NACK) may not be transmitted to the transmitting UE.

Meanwhile, according to an embodiment of the present disclosure, whenscheduling sidelink transmission between different RATs, the followingvarious embodiments may be applied. Here, different RATs may be LTE andNR.

According to an embodiment, when an LTE base station (e.g., eNB)schedules an NR sidelink (e.g., schedules a sidelink transmissionresource based on CG type 1), if the NR sidelink is performed on an NRlicensed carrier, the first transmission timing of the NR sidelink maybe determined based on the TA/2 (e.g., TA refers to timing advance)value between the NR base station (e.g., gNB) and the UE. For example,the first transmission timing of the NR sidelink may be determined basedon

$T_{DCI} - \frac{N_{TA}}{2} + X + {4 \times 10^{- 3}\mspace{14mu}{or}}$$T_{DCI} - \frac{N_{TA}}{2} + X + {\left( {4 + M} \right) \times 1{0^{- 3}.}}$

Also, for example, if the NR sidelink is performed on an ITS dedicatedcarrier, the first transmission timing of the NR sidelink may bedetermined based on the TA/2 value between the LTE base station and theUE. Here, for example, the TA value may be 0 or a pre-configured value.Here, for example, the T_(DCI) may be a start time of a slot in which across-RAT scheduling DCI is received. For example, the X value may be atiming offset value indicated on the cross-RAT scheduling DCI. Forexample, the M value may be a timing offset value on DCI used when theLTE base station schedules mode 3 sidelink transmission to the UE.

According to an embodiment, when an NR base station (e.g., gNB)schedules an LTE sidelink (e.g., schedules a transmission resource basedon a mode 3 SL SPS), if the LTE sidelink is performed on an LTE licensedcarrier, the first transmission timing of the LTE sidelink may bedetermined based on a TA/2 value between the LTE base station (e.g.,eNB) and the UE. For example, the first transmission timing may bedetermined based on

$T_{DCI} - {\frac{N_{TA}}{2} \times T_{s}} + X + {\left( {4 + M} \right) \times 1{0^{- 3}.}}$

Also, for example, if the LTE sidelink is performed on an ITS dedicatedcarrier, the first transmission timing of the NR sidelink may bedetermined based on the TA/2 value between the NR base station (e.g.,gNB) and the UE. Here, for example, the TA value may be 0 or apre-configured value. Here, for example, the T_(S) value may be 1/30720.For example, the NTA value may be a timing offset between uplink and/ordownlink radio frames.

Meanwhile, according to an embodiment of the present disclosure, in thepower limited case, the UE may derive the number of relativelylow-priority PSFCHs (hereinafter, NOTX_NUM) for which transmissionshould be omitted in order to escape the power limited case. Thereafter,for example, the UE may select one from the maximum number of PSFCHsthat the UE can transmit simultaneously (hereinafter, N_MAX) to(N_MAX−NOTX_NUM). Or, for example, the UE may select one from the numberof PSFCHs required to be transmitted (hereinafter, N_REQ) to(N_REQ−NOTX_NUM). The UE may finally transmit the selected number ofPSFCHs and perform power sharing between the selected PSFCHtransmissions. Here, N_MAX may be the maximum number of PSFCHs that theUE can simultaneously transmit FDM. For example, the power limited casemay be a case in which the sum of required power related to PSFCHtransmission required for the UE exceeds the maximum transmit powervalue of the UE. For example, NOTX_NUM may not only include the numberof PSFCHs of low priority, but also may include at least one of thenumber of PSFCHs with relatively loose QoS requirements (e.g., latency,reliability), the number of PSFCHs of the pre-configured HARQ feedbackscheme (e.g., ACK/NACK feedback or feedback transmitting only NACK), thenumber of PSFCHs of ACK information, the number of PSFCHs of NACKinformation, the number of randomly selected PSFCHs, the number ofPSFCHs selected by the UE implementation, for which transmission shouldbe omitted in order to escape the power limited case.

In addition, for example, when the above-described embodiment isapplied, the minimum required performance/condition related to PSFCHtransmission may be guaranteed from a system point of view. For example,the (N_MAX−NOTX_NUM) value and/or the (N_REQ−NOTX_NUM)) value may beconfigured to be greater than or equal to 1. That is, for example, evenin the power limited case, the UE may perform at least one PSFCHtransmission. For example, NOTX_NUM may be configured to a value largerby a pre-configured offset (e.g., 1) than the number of PSFCHs for whichtransmission should be omitted in order to escape the power limitedcase.

For example, according to option A, in the case of the power limitationdescribed above, and if NOTX_NUM is designated as a pre-configurednumber from among N_REQ and N_MAX PSFCH transmissions, the UE may selectone of the numbers from N_MAX to (N_MAX NOTX_NUM) or one from the numberof N_REQ to (N_REQ NOTX_NUM). For example, the UE may preferentiallyselect, from among N_REQ or N MAX PSFCHs, the selected number of PSFCHs(hereinafter, SEL_PSFCHNUM) from PSFCH transmission of relatively highpriority, PSFCH transmission of tight QoS requirements (e.g., latency,reliability), PSFCH transmission of NACK information, PSFCH transmissionof ACK information, PSFCH transmission of pre-configured HARQ feedbackscheme (e.g., NACK-only feedback, ACK/NACK feedback), randomly selectedPSFCH transmission, and PSFCH transmission selected by UEimplementation. For example, the UE may finally perform SEL_PSFCHNUMPSFCH transmissions and power sharing between PSFCH transmissions. Here,for example, the pre-configured number may be any one of a value lessthan or equal to N_REQ, a value less than or equal to N_MAX, a numbercorresponding to a pre-configured ratio (e.g., 50%) among N_REQ PSFCHtransmissions, or a number corresponding to a pre-configured ratio amongN_MAX PSFCH transmissions. For example, the pre-configured number may bea number corresponding to a pre-configured ratio among MIN {N_MAX,N_REQ} (where MIN {X, Y} is a function for deriving a minimum valueamong X and Y). Here, for example, (N_MAX NOTX_NUM) and/or (N_REQNOTX_NUM)) values may be configured to be greater than or equal to 1.

Or, for example, in the power limited case described above, and ifNOTX_NUM is designated as a pre-configured number from among N_REQ andN_MAX PSFCH transmissions, the UE may finally perform power sharingbetween NOTX_NUM PSFCH transmissions. For example, a method of selectingNOTX_NUM from among N_REQ or N_MAX PSFCHs may be the same as a method ofselecting SEL PSFCHNUM from among N_REQ or N_MAX PSFCHs in OPTION Adescribed above. Here, for example, the pre-configured number may be anyone of a value less than or equal to N_REQ, a value less than or equalto N_MAX, a number corresponding to a pre-configured ratio (e.g., 50%)among N_REQ PSFCH transmissions, or a number corresponding to apre-configured ratio among N_MAX PSFCHs transmissions. For example, thepre-configured number may be a number corresponding to a pre-configuredratio among MIN {N_MAX, N_REQ} (where MIN {X, Y} is a function forderiving a minimum value among X and Y). Here, for example, (N_MAXNOTX_NUM) and/or (N_REQ NOTX_NUM)) values may be configured to begreater than or equal to 1.

Or, for example, in the power limited case described above, the UE mayperform at least one of PSFCH transmission with the highest priority,PSFCH transmission with the tightest QoS requirements (e.g., latency,reliability), PSFCH transmission of NACK information, PSFCH transmissionof ACK information, PSFCH transmission of pre-configured HARQ feedbackscheme (e.g., NACK-only feedback, ACK/NACK feedback), randomly selectedPSFCH transmission, or PSFCH transmission selected by UE implementation,from among the N_REQ or N_MAX PSFCH transmissions. Here, for example,when there is a plurality of PSFCH transmissions satisfying theabove-described conditions, the UE may select one of them by UEimplementation.

In addition, for example, whether the above-described embodiment isapplied and/or parameters related to the above-described embodiment maybe configured specifically or differently for at least one of a servicetype, a service type, a priority, a cast type (e.g., unicast, groupcast,broadcast), QoS requirements (e.g., latency, reliability), HARQ feedbackscheme (e.g., NACK-only feedback, ACK/NACK feedback), congestion of theresource pool (e.g., CBR) or the resource pool.

For example, if N_REQ is greater than or equal to N_MAX, and the sum ofrequired transmit power related to N_REQ PSFCHs exceeds the maximumtransmit power value of the UE, the UE may select one of the numbersfrom N_MAX to (N_MAX−NOTX_NUM). Additionally, for example, when atransmit power value related to N_MAX exceeds a maximum transmit powervalue of the UE, the UE may select a PSFCH having a higher priority inN_MAX. For example, the transmit power value related to the PSFCH havinga higher priority selected by the UE may be smaller than the maximumtransmit power of the UE.

For example, when N_REQ is less than N_MAX and the sum of requiredtransmit power related to N_REQ PSFCHs exceeds the maximum transmitpower value of the UE, the UE may select one from N_REQ to (N_REQNOTX_NUM).

According to an embodiment of the present disclosure, when an Open LoopPower Control (OLPC) parameter (e.g., P_O_PSFCH or alpha_PSFCH) thatdetermines the PSFCH power value is not configured, the UE may configureone PSFCH power value as the maximum transmit power value of the UE orthe maximum transmit power allowed on the pre-configured SL carrier. Forexample, the case in which the OLPC parameter is not configured mayinclude a case in which the OLPC parameter is not pre-configured fromthe base station/network. For example, P_O_PSFCH may be a user specificparameter related to the average received SINR related to path loss forthe PSFCH. For example, the alpha_PSFCH value may be a weight valuerelated to path loss for the PSFCH. Here, for example, when the aboveembodiment is applied, if the UE needs to perform a plurality of PSFCHtransmissions, since one PSFCH transmit power value is configured as themaximum transmit power value of the UE, power limited case (e.g., whenthe sum of the required transmit power of a plurality of channelsexceeds the maximum transmit power value of the UE) may occur. At thistime, for example, according to a pre-configured rule (e.g., a rule forsequentially omitting PSFCH transmission of a relatively low priorityuntil it leaves the power limited case) and/or UE implementation, theremay be a problem in that the UE needs to finally transmit one PSFCH or arelatively small number of PSFCHs.

For example, in order to solve the above-mentioned problem, if the OLPCparameter for determining the PSFCH power value is not configured, theUE may equally distribute and share the maximum transmit power value ofthe UE, the maximum transmit power value allowed on the pre-configuredSL carrier, or the pre-configured Uu channel (e.g., PRACH) transmitpower value between a plurality of requested (hereinafter, K_VAL) PSFCHtransmissions.

For example, if the OLPC parameter for determining the PSFCH power valueis not configured, the UE may perform at least one of PSFCH transmissionwith the highest priority, PSFCH transmission with the tightest QoSrequirements (e.g., latency, reliability), PSFCH transmission of NACKinformation, PSFCH transmission of ACK information, PSFCH transmissionof pre-configured HARQ feedback scheme (e.g., NACK-only feedback,ACK/NACK feedback), randomly selected PSFCH transmission, or PSFCHtransmission selected by UE implementation, from among the requiredK_VAL PSFCH transmissions, with the maximum transmit power value of theUE, the maximum transmit power value allowed on the pre-configured SLcarrier, or the pre-configured Uu channel (e.g., PRACH) transmit powervalue. Here, for example, when there is a plurality of PSFCHtransmissions satisfying the above-described conditions, the UE mayselect one of them by UE implementation.

For example, if the OLPC parameter for determining the PSFCH power valueis not configured, the UE may preferentially select at least one ofPSFCH transmission with a pre-configured number of relatively highpriority, PSFCH transmission with the tight QoS requirements (e.g.,latency, reliability), PSFCH transmission of NACK information, PSFCHtransmission of ACK information, PSFCH transmission of pre-configuredHARQ feedback scheme (e.g., NACK-only feedback, ACK/NACK feedback),randomly selected PSFCH transmission, or PSFCH transmission selected byUE implementation, from among the K_VAL PSFCH transmissions. And, forexample, the UE may equally distribute and share the maximum transmitpower value of the UE, the maximum transmit power value allowed on thepre-configured SL carrier, or the pre-configured Uu channel (e.g.,PRACH) transmit power value between the selected PSFCH transmissions.Here, for example, the pre-configured number may be any one of a valueless than or equal to K_VAL, a value less than or equal to N_MAX, anumber corresponding to a pre-configured ratio (e.g., 50%) from amongK_VAL PSFCH transmissions, or a number corresponding to a pre-configuredratio from among N_MAX PSFCH transmissions. For example, thepre-configured number may be a number corresponding to a pre-configuredratio among MIN {N_MAX, K_VAL} (where MIN {X, Y} is a function derivinga minimum value among X and Y).

Here, for example, “required K_VAL PSFCH transmissions” may refer, whenthe number of PSFCH transmissions actually required exceeds the maximumnumber of PSFCHs that can be transmitted simultaneously (hereinafter,K_MAX) of the UE, to K_MAX PSFCH transmissions remaining aftersequentially omitting PSFCH transmissions having a relatively lowpriority. Here, the maximum number of PSFCHs that can be transmittedsimultaneously of the UE may be the maximum number of simultaneouslytransmittable FDM PSFCHs of the UE.

Here, for example, whether the above-described embodiment is appliedand/or parameters related to the above-described embodiment may beconfigured specifically or differently for at least one of a servicetype, a service type, a priority, a cast type (e.g., unicast, groupcast,broadcast), QoS requirements (e.g., latency, reliability), HARQ feedbackscheme (e.g., NACK-only feedback, ACK/NACK feedback), congestion of theresource pool (e.g., CBR) or the resource pool.

According to an embodiment of the present disclosure, the OLPC parameter(e.g., alpha or P_O value) for determining the transmit power of thesidelink channel may be configured specifically or differently for atleast one of a type/kind of MCS table used (e.g., 64 QAM table, 256 QAMtable, low spectral efficiency 64 table), a service type, a servicetype, a priority, a cast type (e.g., unicast, groupcast, broadcast), QoSrequirements (e.g., latency, reliability), HARQ feedback scheme (e.g.,NACK-only feedback, ACK/NACK feedback), congestion of the resource pool(e.g., CBR) or the resource pool. Here, for example, the OLPC parametermay be pre-configured from the base station/network. For example, theMCS table may be an MCS table configured in a resource pool. Forexample, the P_O value may be a user specific parameter related to theaverage received SINR related to path loss. For example, the alpha valuemay be a weight value related to path loss. Here, for example, when theabove-described embodiment is applied, appropriate power control may bepossible according to at least one of spectral efficiency, a selectablemaximum modulation order, and a coding rate. For example, the alphavalue related to the 256 QAM table may be configured to a relativelyhigher value than the alpha value related to the 64 QAM MCS table.

According to an embodiment of the present disclosure, if the number ofRBs related to the resource pool (hereinafter, RB_POOL) is notconfigured in the form of a multiple of the number of RBs related tosubchannels (hereinafter, RB_SCH), when the UE selects/uses the entirenumber of subchannels as its transmission resources, the UE may use RBsderived from MODULO(RB_POOL, RB_SCH) (e.g., MODULO(X,Y) is a functionfor deriving a residual value obtained by dividing X by Y). Or, forexample, if the RB_POOL on the slot is not configured in the form of amultiple of the number of RBs (RB_SCH) related to one subchannel, whenthe UE selects/uses a larger number of subchannels than a pre-configuredthreshold as its transmission resource, the UE may use RBs derived fromMODULO(RB_POOL, RB_SCH). Or, for example, when the RB_POOL on the slotis not configured in the form of a multiple of the number of RBs(RB_SCH) related to one subchannel, when the UE performs transmissionusing the pre-configured MCS table, the UE may use RBs derived fromMODULO(RB_POOL, RB_SCH). Here, for example, the pre-configured MCS tablemay be an MCS table of relatively high spectral efficiency.

According to an embodiment of the present disclosure, a dropping rulebased on a priority between UL TX and SL TX may be configured to comparea UL-related priority indicated by DCI (e.g., 0, 1) with a thresholdvalue related to UL priority or a threshold value related to an SLpriority. Here, for example, the threshold value may be a pre-configuredthreshold value.

Specifically, when the priorities related to the UL URLLC and the EMBBindicated by DCI are all indicated/configured to be lower than or equalto the threshold values related to the UL priority, the UE may performthe dropping rule between the overlapping SL TX and the corresponding ULTX by comparing the UL-related priority indicated by DCI and a thresholdvalue related to the SL priority. For example, the UE may prioritize SLTX if the priority related to SL TX is higher than the correspondingthreshold value, and may prioritize UL TX in other cases. As anotherexample, when the UL URLLC and EMBB related priorities indicated by DCIare all indicated/configured to be higher than the threshold valuesrelated to the UL priority, the UE may perform the dropping rule betweenthe overlapping SL TX and the corresponding UL TX by always prioritizingthe UL TX. For example, the UE may always omit the overlapping SL TX.

As another example, when a priority related to UL URLLC indicated by DCIis indicated/configured higher than a threshold value related to ULpriority, and a priority related to UL EMBB indicated by DCI isindicated/configured lower than a threshold value related to ULpriority, the UE may prioritize transmission related to UL URLLC overoverlapping SL TX. For example, the UE may omit the overlapping SL TX.On the other hand, for example, the UE may perform transmission relatedto UL EMBB only when overlapping SL TX is lower than a threshold valuerelated to UL priority.

According to an embodiment of the present disclosure, when one channeltransmission (e.g., CH_1) overlaps with a plurality of channeltransmissions (e.g., CH_2, CH_3) in the time domain, the prioritybetween the channels may be “CH_3>CH_1>CH_2”, and the transmission starttime in the time domain may be performed in the order of “CH_2, CH_1,CH_3” (e.g., CH_2 and CH_3 do not overlap in the time domain (i.e.,TDM)). Here, for example, in this case, the UE may omit the CH_2transmission, but if the UE does not grasp the scheduling of CH_3transmission and priority information related to CH_3 before performingCH_1 transmission, the UE may skip the CH_3 transmission. For example,in this case, the UE may omit the transmission of the entire CH_2 or thetransmission of the CH_2 symbol overlapping with the CH_1 transmission,but if the UE does not grasp or does not have the ability to grasp thescheduling of the CH_3 transmission and the priority information relatedto CH_3 before performing the CH_1 transmission, the UE may omittransmission of all CH_3 or transmission of CH_3 symbols overlappingwith CH_1 regardless of priority. Or, for example, in this case, the UEmay omit the transmission of the entire CH_2 or the transmission of theCH_2 symbol overlapping with the CH_1 transmission, but if the UE doesnot grasp or does not have the ability to grasp the scheduling of theCH_3 transmission and the priority information related to CH_3 beforeperforming the CH_1 transmission, the UE may omit transmission of theCH_1 symbol overlapping with CH_3. Here, for example, CH_1 may be an SLchannel or a UL channel, and CH_2 and/or CH_3 may be a UL channel or anSL channel. CH_1 may be an SL channel or a UL channel, and CH_2 and/orCH_3 may be a UL channel or an SL channel.

Also, for example, in the above-described situation, it may be assumedthat CH_2 and CH_1 have LCH priorities that the MAC layer canunderstand, and CH_3 does not have LCH priority that the MAC layer canunderstand, but the PHY layer can understand a priority related to CH_3(e.g., the priority value indicated on the SCI related to CH_3, thepre-configured priority value, etc.), and the PHY layer can alsounderstand a priority related to CH_2 and CH_1. Here, for example, insuch a case, the MAC layer may omit or drop CH_2 overlapping with CH_1,deliver only CH_1 to the PHY layer, and the PHY layer that receives thismay omit or drop the transmission of CH_1 overlapping with CH_3.Finally, as only CH_3 transmission is performed, a problem in which CH_3and TDMed CH_2 transmission are unnecessarily omitted may occur. Toalleviate this problem, for example, the PHY layer may provide, to theMAC layer, priority information (e.g., a format related to LCH prioritythat the MAC layer can understand) related to channel/signaltransmission (e.g., CH_3) that cannot be understood by the MAC layer.Through this, for example, in the above-described situation,transmission of CH_2 and CH_3 may be possible. For example, since CH_3has the highest priority, it may possible to preferentially omit or dropCH_1 of lower priority than CH_3, which overlaps with CH_3, whereas, onthe other hand, CH_2, which overlaps with CH_1, and has a lower prioritythan CH_1, may not be omitted or dropped because CH_1 is omitted ordropped.

According to an embodiment of the present disclosure, when the UEre-uses a priority rule (hereinafter, DROP_RULE) between UL TX and SL TXor SL TX and SL TX overlapping on the time domain in order for the UE todetermine transmission to be omitted, as a criteria/rules fordetermining transmission in which transmit power is preferentiallyallocated between UL TX and SL TX or SL TX and SL TX that overlap butcan be transmitted simultaneously in the time domain, the followingexamples may be additionally applied.

For example, transmission to which transmit power is allocatedrelatively preferentially may be regarded as a common/finally relativelyhigh priority in the MAC layer and the PHY layer when theDROP_RULE-based priority is virtually used. For example, when theDROP_RULE-based priority is virtually used, transmission to whichtransmit is most preferentially allocated may be considered as thehighest priority without omission of transmission simultaneously at theMAC layer and the PHY layer or finally at the PHY layer.

For example, if different transmissions considered/understood as thesame priority in the PHY layer are considered/understood astransmissions of different priorities in the MAC layer, the UE maypreferentially allocate transmit power to transmissionconsidered/understood as a relatively high priority in the MAC layer.Or, for example, if different transmissions considered/understood as thesame priority in the MAC layer are considered/understood astransmissions of different priorities in the PHY layer, the UE maypreferentially allocate transmit power to transmissionconsidered/understood as a relatively high priority in the PHY layer.

For example, when direct comparison between the priority used in the PHYlayer (hereinafter, PHY_PRI) and the priority used in the MAC layer(hereinafter, MAC_PRI) is difficult or impossible, informationreplacing/mapping MAC_PRI to PHY_PRI or information replacing/mappingPHY_PRI to MAC_PRI may be configured in a resource pool and/orservice-specific manner by the base station/network. Or, in this case,for example, the PHY layer may report to the MAC layer byreplacing/mapping PHY_PRI related to transmissions for which thepriority is not identified in the MAC layer with MAC_PRI, or the MAClayer may report to the PHY layer by replacing/mapping MAC_PRI relatedto transmissions for which the priority is not identified in the PHYlayer with PHY_PRI. Here, for example, PHY_PRI may be a priority on anassociated SCI or pre-configured priority. For example, MAC_PRI may be apriority related to the LCH.

For example, priority information (i.e., linked/mapped priorityinformation that the PHY layer can understand/grasp) related to atransmission that the PHY layer cannot understand (e.g., when only theMAC layer can understand the priority associated with that transmission)may be configured by the base station/network. Or, for example, priorityinformation (i.e., linked/mapped priority information that the MAC layercan understand/grasp) related to a transmission that the MAC layercannot understand (e.g., when only the PHY layer can understand thepriority associated with that transmission) may be configured by thebase station/network. For example, the priority information may bespecifically configured for at least one of a resource pool, a service,a channel, a signal, or an LCH by a base station/network.

According to an embodiment of the present disclosure, the MAC layer mayselect one TX (hereinafter, MAC_SELTX) based on a pre-configuredprioritization rule among UL TX and SL TX or SL TX and SL TX in whichoverlap occurs in the time domain (e.g., the remaining TX is omitted),and the MAC layer may deliver to the PHY layer along with informationrelated to MAC_SELTX. Here, for example, when an additional overlapoccurs in the time domain between a TX that is not available in the MAClayer or a TX that does not have an associated LCH priority andMAC_SELTX, the PHY layer may select TX to be finally transmitted basedon the information received from the MAC layer.

For example, information related to MAC_SELTX may include at least oneof information that is a UL TX of a higher priority than a thresholdvalue (hereinafter, UL_PTHD) related to a pre-configured UL priority,information that is a UL TX of a lower priority than UL_PTHD orinformation for selecting one TX among the overlapping SL TXs based on athreshold value (hereinafter, SL_PTHD) related to a pre-configured SLpriority.

For example, information related to MAC_SELTX may include at least oneof information that is SL TX of higher priority than pre-configuredSL_PTHD, information that is SL TX of lower priority than SL_PTHD, orinformation for selecting one TX among the overlapping UL TXs based on apre-configured UL_PTHD.

For example, information related to MAC_SELTX may include at least oneof UL_PTHD information and SL_PTHD information.

For example, information related to MAC_SELTX may include at least oneof information instructing to select one from overlapping TXs using bothUL_PTHD and SL_PTHD, information instructing to select one fromoverlapping TXs using SL_PTHD according to the LTE V2X rule, orinformation instructing to select one from overlapping TXs using thethreshold value related to the SL priority configured independently.

For example, the information related to MAC_SELTX may include at leastone of the LCH priority information of UL TX, pre-configured prioritycorresponding to the LCH priority information of the UL TX, thresholdinformation related to the priority which is pre-configured to the LCHpriority information of the UL TX, LCH priority information of SL TX,pre-configured priority corresponding to the LCH priority information ofthe SL TX, or threshold information related to the priority which ispre-configured to the LCH priority information of the SL TX.

According to an embodiment of the present disclosure, if transmission(hereinafter, ULTX_SLINF) of pre-configured SL information (e.g., SLHARQ feedback, SL BSR/SR) based on a UL channel (e.g., PUCCH) overlapswith the pre-configured SL channel transmission (hereinafter,SLTX_SLINF) in the time domain, the UE may select the final transmission(e.g., omit the remaining transmission) according to the following rule.Or, for example, in this case, in the power limited case (e.g., asituation in which the sum of required power of channels required to betransmitted exceeds the maximum transmit power value of the UE), the UEmay preferentially allocate power between the UL channel and the SLchannel. Here, for example, the above-described simultaneoustransmission of the UL channel and the SL channel may not be performeddue to the RF capability limit of the UE. Also, for example, theabove-described simultaneous transmission of the UL channel and the SLchannel may be performed by the UE on the same carrier. Alternatively,for example, the above-described simultaneous transmission of UL channeland SL channel may be performed by the UE on different carriers. Asanother example, the proposed rule of this embodiment may be appliedwhen UL information (e.g., UL SCH) is transmitted through a UL channel,and the UL information overlaps with SLTX_SLINF transmission in a timedomain. Here, for example, the UL information may be pre-configured ULinformation rather than SL information. For example, the proposed ruleof this embodiment may be applied when SL/UL information is transmittedtogether (e.g., UL SCH and SL HARQ feedback, or UL SCH and SL BSR)through a UL channel (e.g., considered as ULTX_SLINF for convenience ofdescription), and SL/UL information overlaps with SLTX_SLINFtransmission in the time domain.

For example, when a priority related to ULTX_SLINF transmission is thesame as a priority of SLTX_SLIN, the UE may prioritize ULTX_SLINFtransmission (e.g., omit SLTX_SLIN transmission). For example, when thepriority related to ULTX_SLINF transmission is the same as the priorityof SLTX_SLIN, the UE may prioritize SLTX_SLIN transmission (e.g., omitULTX_SLINF transmission). Or, for example, in the power limited case,the UE may prioritize the allocation of required power related toULTX_SLINF transmission. For example, in the power limited case, the UEmay prioritize the allocation of required power related to SLTX_SLINtransmission. Or, for example, the UE may select a preferredtransmission with the UE implementation or randomly. Here, for example,the application of the above-mentioned rule may be, when the priorityrelated to SL information on ULTX_SLINF overlapping in the time domainand the priority of SL information related to SLTX_SLINF are the same,prioritizing SL information transmitted through the UL channel (or SLchannel). For example, application of the above-mentioned rule may be,when the priority related to SL information on ULTX_SLINF overlapping inthe time domain and the priority of SL information related to SLTX_SLINFare the same, prioritizing SL information transmitted through the SLchannel. As another example, when the priority related to ULTX_SLINFtransmission and the priority of SLTX_SLIN are different, the UE mayprioritize transmission of a relatively high priority.

For example, whether the above-mentioned rule is applied or not, orparameters related to the above-mentioned rule may be configuredspecifically or differently for at least one of resource pool, servicetype, priority, QoS requirements (e.g., packet/traffic related to URLLC,packet/traffic related to EMBB, reliability, latency), cast type (e.g.,unicast, groupcast, broadcast), resource pool congestion level (e.g.,CBR), SL HARQ feedback scheme (e.g., feedback that transmits only NACK,ACK/NACK feedback), SL channel/signal type related to SLTX_SLINF (e.g.,PSSCH/PSCCH, PSFCH, SL SSB), UL channel/signal type related toULTX_SLINF (e.g., PUCCH, PUSCH).

According to an embodiment of the present disclosure, when a thresholdvalue related to SL priority (hereinafter, SL_PTHD) or a threshold valuerelated to UL priority (hereinafter, UL_PTHD)) is not configured fromthe base station/network, according to the following rule, the UE maydetermine priority among UL channel-based transmission or UL informationtransmission and SL channel-based transmission or SL informationtransmission that overlap in the time domain. Here, for example,transmission regarded as a relatively high priority may be configured toto perform actual transmission (e.g., transmission of a low priority isomitted). Or, for example, in the power limited case (e.g., a situationin which the sum of required power of channels required to betransmitted exceeds the maximum transmist power value of the UE),transmission regarded as a relatively high priority may be configured tobe preferentially allocated required transmit power.

For example, whether the above-mentioned rule is applied or not, orparameters related to the above-mentioned rule may be configuredspecifically or differently for at least one of resource pool, servicetype, priority, QoS requirements (e.g., packet/traffic related to URLLC,packet/traffic related to EMBB, reliability, latency), cast type (e.g.,unicast, groupcast, broadcast), resource pool congestion level (e.g.,CBR), SL HARQ feedback scheme (e.g., feedback that transmits only NACK,ACK/NACK feedback), SL channel/signal type related to SLTX_SLINF (e.g.,PSSCH/PSCCH, PSFCH, SL SSB), UL channel/signal type related toULTX_SLINF (e.g., PUCCH, PUSCH).

For example, when both SL_PTHD and UL_PTHD are not configured, the UEmay always prioritize UL channel-based transmission or UL informationtransmission over SL channel-based transmission or SL informationtransmission. Or, for example, when both SL_PTHD and UL_PTHD are notconfigured, the UE may always prioritize SL channel-based transmissionor SL information transmission over UL channel-based transmission or ULinformation transmission.

For example, if both SL_PTHD and UL_PTHD are not configured, the UE mayprioritize UL channel-based transmission or UL information transmissionindicated with “HIGH” priority through predefined signaling (e.g., DCI,RRC) from the base station/network over SL channel-based transmission orSL information transmission. And, the UE may de-prioritize ULchannel-based transmission or UL information transmission indicated with“LOW” priority through predefined signaling (e.g., DCI, RRC) from thebase station/network over SL channel-based transmission or SLinformation transmission.

For example, when neither SL_PTHD nor UL_PTHD is configured, the UE maydetermine which transmission to prioritize according to UEimplementations or may give priority to randomly selected transmission.

For example, if only UL_PTHD is configured, the UE may prioritize ULchannel-based transmission or UL information transmission with higherpriority than UL_PTHD over SL channel-based transmission or SLinformation transmission, and the UE may regard the other ULchannel-based transmission or UL information transmission as a lowerpriority compared to the SL channel-based transmission or SL informationtransmission. For example, if only UL_PTHD is configured, the UE mayprioritize UL channel-based transmission or UL information transmissionwith higher priority than UL_PTHD over SL channel-based transmission orSL information transmission, and the UE may regard the other ULchannel-based transmission or UL information transmission as a higherpriority than the SL channel-based transmission or SL informationtransmission. For example, when only UL_PTHD is configured, the UE maydetermine which transmission to prioritize according to UEimplementation, or may prioritize randomly selected transmission. Forexample, when only UL_PTHD is configured, the UE may exceptionallyprioritize UL channel-based transmission or UL information transmissionindicated with “HIGH” priority through predefined signaling from thebase station/network over SL channel-based transmission or SLinformation transmission. For example, when only UL_PTHD is configured,the UE may always prioritize UL channel-based transmission or ULinformation transmission over SL channel-based transmission or SLinformation transmission. For example, when only UL_PTHD is configured,the UE may always prioritize SL channel-based transmission or SLinformation transmission over UL channel-based transmission or ULinformation transmission.

For example, if only SL_PTHD is configured, the UE may prioritize SLchannel-based transmission or SL information transmission with higherpriority than SL_PTHD over UL channel-based transmission or ULinformation transmission, and the UE may regard the other SLchannel-based transmission or SL information transmission as a lowerpriority compared to the UL channel-based transmission or UL informationtransmission. For example, if only SL_PTHD is configured, the UE maydetermine which transmission to prioritize according to UEimplementation, or may prioritize randomly selected transmission. Forexample, when only SL_PTHD is configured, the UE may exceptionallyprioritize UL channel-based transmission or UL information transmissionindicated with “HIGH” priority through predefined signaling from thebase station/network over SL channel-based transmission or SLinformation transmission. For example, with respect to SL channel-basedtransmission or SL information transmission having a higher prioritythan SL_PTHD, the UE may exceptionally prioritize UL channel-basedtransmission or UL information transmission indicated with “HIGH”priority.

For example, when only SL_PTHD is configured, the UE may alwaysprioritize SL channel-based transmission or SL information transmissionover UL channel-based transmission or UL information transmission. Or,for example, when only SL_PTHD is configured, the UE may alwaysprioritize UL channel-based transmission or UL information transmissionover SL channel-based transmission or SL information transmission.

According to an embodiment of the present disclosure, the SL BWPconfiguration may be in the form of a sub-set of the UU BWP. Forexample, the SL BWP configuration may be in the form of a sub-set of UuBWP in terms of RF bandwidth while the center frequency, DC carrier, orDC sub-carrier position is the same as Uu BWP. For example, whenswitching between the SL BWP and the active Uu BWP, an interruption timeof communication may not be required. Here, for example, “Uu BWP” mayinclude an activated UL BWP, an activated DL BWP, a default UL BWP, adefault DL BWP, an initial UL BWP, or an initial DL BWP. For example,when the Uu BWP is reset/changed, if the above-described relationshipcondition is not satisfied, it may be configured to deactivate the SLBWP or stop the SL communication based on the SL BWP. Or, for example,when the Uu BWP is reset/changed, if the condition of theabove-described relationship is not satisfied, it may be configured todeactivate the Uu BWP or stop Uu communication based on the Uu BWP.

According to an embodiment of the present disclosure, when the UEperforms mode 1 CG resource-based PSCCH/PSSCH transmission, the value ofthe resource reservation period field and/or the size of the resourcereservation period field on the SCI related to the PSCCH/PSSCH may bepre-configured to specify a specific value. For example, when the UEperforms mode 1 CG resource-based PSCCH/PSSCH transmission, whilemaintaining the value of the mode 1 resource reservation period fieldand/or the size of the resource reservation period field on the SCIrelated to the PSCCH/PSSCH to be the same as the size (e.g., 4 bits) ofthe resource reservation period field on the SCI related to the mode 2operation, but may be configured to be designated as a pre-configuredspecific value (e.g., 0000) irrespective of the associated CG resourcereservation period. Here, for example, the above-described embodimentmay be applied when some or all of the mode 1/2 resource pool do notoverlap. For example, the above-described embodiment may be applied whenthe UE performs, on a licensed carrier or an ITS-dedicated carrier inwhich a base station does not exist, a mode 1 CG resource-basedPSCCH/PSSCH transmission in a pre-configured resource pool of mode 1.Also, for example, when the UE performs PSCCH/PSSCH transmission basedon mode 1 CG resources, at least one of the presence or absence of themode 1 resource reservation period field on the SCI related toPSCCH/PSSCH, the size of the resource reservation period field, and themethod of specifying the resource reservation period field value (e.g.,whether to designate the corresponding field value as the reservationperiod of the associated CG resource or whether to specify/fix as aspecific value pre-configured from the base station (e.g., 0000)), orinformation related to a resource reservation period field value may bespecifically informed to the UE by the base station through predefinedsignaling, according to tat least one of resource pool, priority ofservice, or service type.

According to an embodiment of the present disclosure, when the UEtransmits a plurality of PSFCHs within the maximum number that can betransmitted simultaneously, if the number of PSFCHs transmitted by CDMis different for each RB (e.g., a plurality of PSFCH sequences istransmitted on RB #X by CDM and only one PSFCH sequence is transmittedon RB#Y), the allocated or required transmit power value varies betweenRBs used for PSFCH transmission, so that a problem such as an increasein MPR may occur from the RF side. In order to solve this problem, forexample, the UE may allocate related RBs in descending order of priorityfrom PSFCH with the highest priority or PSFCH with a relatively highpriority among a plurality of PSFCHs requiring simultaneoustransmission, and when an additional PSFCH (hereinafter, POST_PSFCH)allocation is required to an RB to which the PSFCH has already beenallocated, the UE may omit transmission of the POST_PSFCH. Or, forexample, for a plurality of PSFCHs requiring simultaneous transmission,the UE allocates all related RBs in descending order of priority fromthe PSFCH with the highest priority or the PSFCH with a relatively highpriority, and if there are RBs to which a plurality of PSFCHtransmissions are allocated, the UE may omit the remaining PSFCHtransmissions except for the highest-priority PSFCH transmission. Forexample, after replacing the omitted PSFCH with a PSFCH to which an RBhas not been allocated due to a low priority, the UE may map thereplaced PSFCH to each related RB, and may repeatedly perform proceduressuch as PSFCH allocation for each RB, PSFCH transmission omission basedon number/priority and replacement with PSFCH to which an RB has notbeen allocated, etc.

According to an embodiment of the present disclosure, a PSFCH overheadindicator (e.g., 1 bit or 2 bits) used for PSSCH Transport Block Size(TBS) determination may be configured to be masked to CRC related to 1stSCI or 2nd SCI. For example, the UE may mask the PSFCH overheadindicator used for determining the PSSCH TBS to the CRC related to the1st SCI or the 2nd SCI transmitted through the PSCCH. Also, for example,when calculating/deriving an upper limit value of the number of REs usedfor 2nd SCI mapping, a pre-configured SL CSI-RS overhead may beexcluded. For example, when the UE calculates/derives the upper limit ofthe number of REs used for 2nd SCI mapping, the UE may always exclude apre-configured virtual SL CSI-RS overhead. Or, for example, whencalculating/deriving the upper limit of the number of REs used for the2nd SCI mapping, the overhead of the SL CSI-RS may not beexcluded/considered. For example, when the UE calculates/derives theupper limit value of the number of REs used for 2nd SCI mapping, the UEmay not exclude/consider the pre-configured SL CSI-RS actual overhead.For example, if the REs used for the 2nd SCI mapping and the SL CSI-RSmapping do not overlap (e.g., the 2nd SCI mapping symbol and the SLCSI-RS mapping symbol are TDMed), when calculating/deriving the upperlimit of the number of REs used for the 2nd SCI mapping, the overhead ofthe SL CSI-RS may not be excluded/considered. For example, whether toapply the present embodiment or parameters related to the embodiment maybe configured specifically or differently for at least one of PSSCHmodulation order, PSSCH-related MCS coding rate, PSSCH-related MCStarget coding rate, 2nd SCI a beta offset value related to determiningthe number of REs mapped to 2nd SCI coding rate.

According to an embodiment of the present disclosure, when PSFCH TX/RXoperations overlap at the same time point, it may be configured toprioritize PSFCH transmission or reception operations based on arelatively large number of PSFCHs. For example, when PSFCH TX/RXoperations overlap at the same time point, after comparing the number ofTXs related to the PSFCH with the highest priority and the number of RXsrelated to the PSFCH with the highest priority, it may be configured toprioritize PSFCH transmission or reception operations based on arelatively large number of PSFCHs. For example, when PSFCH TX/RXoperations overlap at the same time point, after comparing the number ofTXs related to a PSFCH or session with a higher priority than apre-configured threshold and the number of RXs related to a PSFCH orsession with a higher priority than a pre-configured threshold, it maybe configured to prioritize PSFCH transmission or reception operationsbased on a relatively large number of PSFCHs. Here, for example, thepriority may include a priority related to the service. For example,when PSFCH TX/RX operations overlap at the same time point, aftercomparing the session with the largest number of PSFCH TXs and thesession with the largest number of PSFCH RXs, it may be configured toprioritize PSFCH transmission or reception based on a relatively largenumber of PSFCHs. For example, when PSFCH TX/RX operations overlap atthe same time point, after determining to perform the PSFCH transmissionor reception operation based on a relatively high priority for eachsession, the number of sessions in which the PSFCH RX operation isperformed and the number of sessions in which the PSFCH TX operation iscompared, and it may be configured to prioritize PSFCH transmission orreception based on a relatively large number of PSFCHs. Here, therelatively high priority may be replaced with the highest priority. Forexample, when PSFCH TX/RX operations overlap at the same time point,more weight may be applied to the number of PSFCH TXs or PSFCH RXsrelated to groupcast compared to unicast. Or, for example, when PSFCHTX/RX operations overlap at the same time point, more weight may beapplied to the number of PSFCH TXs or PSFCH RXs related to unicastcompared to groupcast. Here, the weight may be a weight related toscale-up or a weight related to scale-down.

According to an embodiment of the present disclosure, it may beconfigured to assume the following overhead when deriving SL CSIinformation on a time/frequency resource designated as an SL CSIreference resource. Or, for example, it may be configured to exclude thefollowing overhead when deriving SL CSI information on a time/frequencyresource designated as an SL CSI reference resource. Here, for example,it may be assumed that the SL CSI reference resource on the time domainis the SL SLOT in which the PSSCH/PSCCH triggering the SL CSI reportingis received. Also, for example, it may be assumed that the SL CSIreference resource on the frequency domain is a scheduled PRB related tothe PSSCH triggering the SL CSI report. In addition, for example, in thepresent disclosure, whether to apply the above-described rule orparameters (e.g., an overhead value assumed when deriving SL CSIinformation) related to whether to apply the above-described rule may beconfigured differently or independently for at least one of servicetype, priority, QoS requirements (e.g., reliability, latency), resourcepool congestion level (e.g., CBR), sidelink mode (e.g., mode 1, mode 2),resource pool, whether it is PSFCH slot or non-PSFCH slot, PSSCHmodulation order, PSSCH modulation order triggering SL CSI report, betaoffset value determining the number of REs mapped to 2nd SCI, betaoffset value determining the number of REs mapped to 2nd SCI applied onPSSCH triggering SL CSI report or the number of SL CSI-RS ports.

For example, the overhead of the PSFCH resource (e.g., PSFCH symbol) maybe configured to be assumed to be the PSCCH (e.g., 1st SCI) triggeringSL CSI reporting. For example, it may be configured that the overhead ofthe PSFCH resource (e.g., PSFCH symbol) is assumed to be a value (e.g.,the PSFCH resource overhead used for TBS determination of the PSSCH)indicated on the PSSCH (e.g., 2nd SCI).

Here, for example, on PSCCH (e.g., 1st SCI) or PSSCH (e.g., 2nd SCI),when the overhead value of the PSFCH resource used for PSSCH TBSdetermination is not signaled, exceptionally, it may be assumed that thePSSCH/PSCCH triggering the SL CSI report is an overhead value of anactual PSFCH resource on a received slot. Or, for example, on PSCCH(e.g., 1st SCI) or PSSCH (e.g., 2nd SCI), when the overhead value of thePSFCH resource used for PSSCH TBS determination is not signaled, anoverhead value of the average PSFCH resource on the resource pool may beassumed. Here, for example, the overhead value of the average PSFCHresource on the resource pool may be replaced with the overhead value ofthe largest PSFCH resource on the resource pool, the overhead value ofthe smallest PSFCH resource on the resource pool, or the overhead valueof the pre-configured PSFCH resource. Or, for example, on PSCCH (e.g.,1st SCI) or PSSCH (e.g., 2nd SCI), if the overhead value of the PSFCHresource used for PSSCH TBS determination is not signaled, it may beconfigured so that the overhead of the PSFCH resource is notassumed/used for deriving SL CSI information. For example, on PSCCH(e.g., 1st SCI) or PSSCH (e.g., 2nd SCI), when the overhead value of thePSFCH resource used for PSSCH TBS determination is not signaled, the UEmay not assume/use the overhead of the PSFCH resource for deriving SLCSI information. Here, for example, on PSCCH (e.g., 1st SCI) or PSSCH(e.g., 2nd SCI), a case where the overhead value of the PSFCH resourceused for PSSCH TBS determination is not signaled may include a casewhere the PSFCH resource is not configured, a case where the PSFCHresource period is 1 slot, or a case where the PSFCH resource period isconfigured to a value equal to or less than a pre-configured thresholdvalue (e.g., 2 slots).

For example, the PSSCH DMRS overhead (e.g., DMRS RE/symbol) may beconfigured to be assumed to be the average number of DMRS REs related tothe PSSCH triggering SL CSI reporting. For example, the average numberof DMRS REs related to PSSCH triggering SL CSI reporting may be theaverage number of DMRS REs used for TBS determination.

For example, the overhead related to the 2nd SCI and/or the overheadrelated to the PSCCH may be configured to be assumed to be a valueactually applied on the PSSCH/PSCCH triggering the SL CSI report and/ora value used to determine the TBS related to the PSSCH.

FIG. 11 illustrates a procedure for a receiving UE to transmit N PSFCHsto a transmitting UE according to an embodiment of the presentdisclosure. The embodiment of FIG. 11 may be combined with variousembodiments of the present disclosure.

Referring to FIG. 11, in step S1110, the transmitting UE may transmit atleast one PSCCH to the receiving UE. In step S1120, the transmitting UEmay transmit at least one PSSCH related to at least one PSCCH to thereceiving UE.

For example, based on the at least one PSSCH overlapping with the firstchannel and the second channel in the time domain, at least one of theat least one PSSCH, the first channel, or the second channel may beomitted. Here, for example, the first channel may lead the most in thetime domain and the second channel may trail the most in the timedomain. For example, among priorities related to channels, the priorityrelated to the first channel may be the lowest, and the priority relatedto the second channel may be the highest. In this case, for example,based on the failure of the transmitting UE to identify the priorityrelated to the second channel, the first channel and the second channelmay be omitted regardless of the priority related to the channels. Or,for example, based on the failure of the MAC layer of the transmittingUE to identify the priority related to the second channel, informationon the priority related to the second channel may be transmitted fromthe PHY layer of the transmitting UE to the MAC layer of thetransmitting UE. For example, at least one PSSCH may be omitted based onthe information on priority related to the second channel.

For example, at least one PSSCH may include at least one SCI. Forexample, the at least one SCI may be a 2nd SCI. For example, the numberof Resource Elements (REs) used to map at least one SCI may becalculated by the transmitting UE. In this case, the calculation of thenumber of REs may be performed without considering an overhead relatedto a pre-configured SL Channel State Information (CSI) Reference Signal(RS).

For example, the size of a transport block related to at least one PSSCHmay be determined based on an indicator related to a PSFCH overhead. Forexample, the Cyclic Redundancy Check (CRC) related to the at least oneSCI may include an indicator related to the PSFCH overhead.

In step S1130, the receiving UE may determine the resource related to atleast one PSFCH based on the index of the slot and the index of thesubchannel related to the at least one PSSCH.

For example, the overhead related to at least one PSFCH resource may notbe used for derivation of sidelink CSI information. For example, thesidelink CSI information may be derived on a reference resource relatedto the sidelink CSI. For example, the reference resource related to thesidelink CSI may be a sidelink slot in which at least one of a PSCCH ora PSSCH triggering a sidelink SCI report is received. For example, thereference resource related to the sidelink CSI may be a PhysicalResource Block (PRB) related to the PSSCH triggering the sidelink CSIreport.

In step S1140, the receiving UE may select/determine N PSFCHs from amongthe at least one PSFCH, based on the sum of power required to transmitat least one PSFCH being greater than the maximum transmit power of thereceiving UE. For example, N may be selected from the number of PSFCHtransmissions having a high priority among the maximum number of PSFCHtransmissions to the maximum number of PSFCH transmissions. For example,N may be an integer of 1 or more. For example, transmit power related toPSFCH transmission having a high priority may be less than or equal tothe maximum transmit power of the receiving UE. For example, N may beautonomously selected by the receiving UE.

For example, based on the number of PSFCHs scheduled for the receivingUE being greater than the maximum number of PSFCHs that the receiving UEcan transmit, the maximum number of PSFCH transmissions may be themaximum number of PSFCHs that the receiving UE can transmit.

For example, based on the number of PSFCHs scheduled for the receivingUE being smaller than the maximum number of PSFCHs that the receiving UEcan transmit, the maximum number of PSFCH transmissions may be thenumber of PSFCHs scheduled for the receiving UE.

In step S1150, the receiving UE may determine the transmit power for theN PSFCHs. For example, based on parameters related to Open Loop PowerControl (OLPC) for determining the transmit power for the PSFCH beingnot configured to the receiving UE, the transmit power for the PSFCH maybe configured to the maximum transmit power value of the receiving UE.For example, the N PSFCH transmit powers may equally share the maximumtransmit power value of the receiving UE. That is, for example, thereceiving UE may equally distribute the maximum transmit power of thereceiving UE to the N PSFCH transmit powers.

In step S1160, the receiving UE may transmit N PSFCHs to thetransmitting UE based on the transmit power.

FIG. 12 illustrates a method for a UE to select N from at least onePSFCH according to an embodiment of the present disclosure. Theembodiment of FIG. 12 may be combined with various embodiments of thepresent disclosure.

For example, FIG. 12 specifically shows step S1150 of FIG. 11. Referringto FIG. 12, in step S1210, the UE may determine at least one PSFCH. Instep S1220, based on the sum of power required to transmit at least onePSFCH being greater than the maximum transmit power of the receiving UE,the UE may determine whether the number of scheduled PSFCHs is less thanor equal to the maximum number of PSFCHs that can be transmitted. Forexample, the number of scheduled PSFCHs is the number of scheduledPSFCHs for the UE, and may be the number of PSFCHs required for the UE.For example, the maximum number of PSFCHs that can be transmitted may bethe maximum number of PSFCHs that the UE can transmit simultaneouslythrough FDM.

For example, if the number of scheduled PSFCHs is less than or equal tothe maximum number of PSFCHs that can be transmitted, in step S1230, theUE may determine whether the transmit power related to the number ofscheduled PSFCHs is less than or equal to the maximum transmit power ofthe UE. For example, when the transmit power related to the number ofscheduled PSFCHs is less than or equal to the maximum transmit power ofthe UE, in step S1250, the UE may select the number of scheduled PSFCHsas N. Or, for example, if the transmit power related to the number ofscheduled PSFCHs is greater than the maximum transmit power of the UE,in step S1260, the UE may autonomously select N from among the number ofscheduled PSFCHs, from the number of PSFCHs with high priority to thenumber of scheduled PSFCHs.

For example, if the number of scheduled PSFCHs is greater than themaximum number of PSFCHs that can be transmitted, in step S1240, the UEmay determine whether the transmit power related to the maximum numberof PSFCHs that can be transmitted is less than or equal to the maximumtransmit power of the UE. For example, when the transmit power relatedto the maximum number of PSFCHs that can be transmitted is less than orequal to the maximum transmit power of the UE, in step S1270, the UE mayselect the maximum number of PSFCHs that can be transmitted as N. Or,for example, when the transmit power related to the maximum number ofPSFCHs that can be transmitted is greater than the maximum transmitpower of the UE, in step S1280, the UE may autonomously select N fromamong the maximum number of PSFCHs that can be transmitted, from thenumber of PSFCHs with high priority to the maximum number of PSFCHs thatcan be transmitted.

FIG. 13 illustrates an example in which an SL channel overlaps with aplurality of channels according to an embodiment of the presentdisclosure. The embodiment of FIG. 13 may be combined with variousembodiments of the present disclosure.

Referring to FIG. 13, for example, at least one PSSCH of FIG. 11 mayinclude an SL channel. For example, the SL channel may overlap with thefirst UL channel and the second UL channel in the time domain. In thiscase, the UE may omit at least one of the SL channel, the first ULchannel, and the second UL channel.

For example, the priority related to the first UL channel may be thelowest and the priority related to the second UL channel may be thehighest. That is, the priority related to the SL channel may be higherthan the priority related to the first UL channel and lower than thepriority related to the second UL channel. In this case, for example,the UE may not be able to identify the priority related to the second ULchannel that follows in time. In this case, for example, the UE may omitthe first UL channel and the second UL channel regardless of thepriority related to the channels.

Alternatively, for example, the MAC layer of the UE may identify thepriority related to the first UL channel and the priority related to theSL channel, but may not identify the priority related to the second ULchannel. Here, for example, the priority may be a priority related tothe LCH. For example, when the PHY layer of the UE identifies thepriority related to the second channel, the PHY layer of the UE maytransmit information on the priority related to the second channel tothe MAC layer of the UE. Accordingly, the UE may omit the SL channelbased on the information on the priority related to the second channel.

FIG. 14 illustrates a method for a first device to transmit N PSFCHsaccording to an embodiment of the present disclosure. The embodiment ofFIG. 14 may be combined with various embodiments of the presentdisclosure.

Referring to FIG. 14, in step S1410, the first device 100 may receive atleast one PSCCH. In step S1420, the first device 100 may receive atleast one PSSCH related to at least one PSCCH.

For example, based on the at least one PSSCH overlapping with the firstchannel and the second channel in the time domain, at least one of theat least one PSSCH, the first channel, or the second channel may beomitted. For example, the first channel may lead the most in the timedomain and the second channel may trail the most in the time domain. Forexample, among priorities related to channels, the priority related tothe first channel may be the lowest, and the priority related to thesecond channel may be the highest. In this case, for example, based onthe priority related to the second channel not being identified, thefirst channel and the second channel may be omitted regardless of thepriority related to the channels. Or, for example, based on the priorityrelated to the second channel not being identified by the MAC layer,information on the priority related to the second channel may betransmitted from the PHY layer to the MAC layer. In this case, forexample, at least one PSSCH may be omitted based on the information onpriority related to the second channel.

For example, at least one PSSCH may include at least one SCI. Forexample, the number of Resource Elements (REs) used to map at least oneSCI may be calculated. For example, the calculation of the number of REsmay be performed without considering an overhead related to apre-configured SL CSI-RS. For example, the size of a transport blockrelated to at least one PSSCH may be determined based on an indicatorrelated to a PSFCH overhead. For example, the Cyclic Redundancy Check(CRC) related to the at least one SCI may include an indicator relatedto the PSFCH overhead.

For example, the overhead related to at least one PSFCH resource may notbe used for derivation of sidelink CSI information. For example, thesidelink CSI information may be derived on a reference resource relatedto the sidelink CSI. For example, the reference resource related to thesidelink CSI may be a sidelink slot in which at least one of a PSCCH ora PSSCH triggering a sidelink SCI report is received. For example, thereference resource related to the sidelink CSI may be a PhysicalResource Block (PRB) related to the PSSCH triggering the sidelink CSIreport.

In step S1430, the first device 100 may determine a resource related toat least one PSFCH based on an index of a slot and an index of asubchannel related to at least one PSSCH.

In step S1440, the first device 100 may determine N PSFCHs from amongthe at least one PSFCH based on the sum of power required to transmitthe at least one PSFCH being greater than the maximum transmit power ofthe first device 100. For example, N may be selected from the number ofPSFCH transmissions with high priority among the maximum number of PSFCHtransmissions, to the maximum number of PSFCH transmissions. Forexample, N may be an integer of 1 or more. For example, the transmitpower related to PSFCH transmission having a high priority may be lessthan or equal to the maximum transmit power of the first device 100. Forexample, based on the number of PSFCHs scheduled to the first device 100being greater than the maximum number of PSFCHs that the first device100 can transmit, the maximum number of PSFCH transmissions may be themaximum number of PSFCHs that the first device 100 can transmit. Forexample, based on the number of PSFCHs scheduled to the first device 100being smaller than the maximum number of PSFCHs that the first device100 can transmit, the maximum number of PSFCH transmissions may be thenumber of PSFCHs scheduled to the first device 100. For example, N maybe autonomously selected by the first device 100. For example, thetransmit power value of each of the N PSFCHs may be a value in which themaximum transmit power value of the first device 100 is equally shared.

In step S1450, the first device 100 may determine the transmit power forthe N PSFCHs. For example, based on parameters related to Open LoopPower Control (OLPC) that determines the transmit power for the PSFCHbeing not configured to the first device 100, the transmit power for thePSFCH may be configured to a maximum transmit power value of the firstdevice 100.

In step S1460, the first device 100 may transmit N PSFCHs based on thetransmit power.

The above-described embodiment may be applied to various devices to bedescribed below. For example, the processor 102 of the first device 100may control the transceiver 106 to receive at least one PSCCH. Inaddition, the processor 102 of the first device 100 may control thetransceiver 106 to receive at least one PSSCH related to the at leastone PSCCH. In addition, the processor 102 of the first device 100 maydetermine a resource related to at least one PSFCH based on an index ofa slot and an index of a subchannel related to at least one PSSCH. Inaddition, the processor 102 of the first device 100 may determine thetransmit power for N PSFCHs. In addition, the processor 102 of the firstdevice 100 may control the transceiver 106 to transmit N PSFCHs based onthe transmit power.

According to an embodiment of the present disclosure, a first device forperforming wireless communication may be provided. For example, thefirst device may include one or more memories for storing instructions;one or more transceivers; and one or more processors connecting the oneor more memories and the one or more transceivers. For example, the oneor more processors may execute the instructions to receive at least onephysical sidelink control channel (PSCCH), receive at least one physicalsidelink shared channel (PSSCH) related to the at least one PSCCH,determine a resource related to at least one physical sidelink feedbackchannel (PSFCH) based on an index of a slot and an index of a subchannelrelated to at least one PSSCH, determine N PSFCHs from among the atleast one PSFCH based on the sum of power required to transmit the atleast one PSFCH being greater than the maximum transmit power of thefirst device, wherein N is selected from the number of PSFCHtransmissions with high priority among the maximum number of PSFCHtransmissions, to the maximum number of the PSFCH transmissions,determine transmit power for N PSFCHs, and transmit N PSFCHs based onthe transmit power. For example, N may be an integer of 1 or more. Forexample, the transmit power related to the PSFCH transmissions with highpriority may be less than or equal to the maximum transmit power of thefirst device.

According to an embodiment of the present disclosure, an apparatusconfigured to control the first UE may be provided. For example, theapparatus may include one or more processors; and one or more memoriesoperably coupled to the one or more processors and storing instructions.For example, the one or more processors may execute the instructions toreceive at least one physical sidelink control channel (PSCCH), receiveat least one physical sidelink shared channel (PSSCH) related to the atleast one PSCCH, determine a resource related to at least one physicalsidelink feedback channel (PSFCH) based on an index of a slot and anindex of a subchannel related to at least one PSSCH, determine N PSFCHsfrom among the at least one PSFCH based on the sum of power required totransmit the at least one PSFCH being greater than the maximum transmitpower of the first UE, wherein N is selected from the number of PSFCHtransmissions with high priority among the maximum number of PSFCHtransmissions, to the maximum number of the PSFCH transmissions,determine transmit power for N PSFCHs, and transmit N PSFCHs based onthe transmit power. For example, N may be an integer of 1 or more. Forexample, the transmit power related to the PSFCH transmissions with highpriority may be less than or equal to the maximum transmit power of thefirst UE.

According to an embodiment of the present disclosure, a non-transitorycomputer-readable storage medium recording instructions may be provided.For example, the instructions, when executed, may cause the first deviceto: receive at least one physical sidelink control channel (PSCCH),receive at least one physical sidelink shared channel (PSSCH) related tothe at least one PSCCH, determine a resource related to at least onephysical sidelink feedback channel (PSFCH) based on an index of a slotand an index of a subchannel related to at least one PSSCH, determine NPSFCHs from among the at least one PSFCH based on the sum of powerrequired to transmit the at least one PSFCH being greater than themaximum transmit power of the first UE, wherein N is selected from thenumber of PSFCH transmissions with high priority among the maximumnumber of PSFCH transmissions, to the maximum number of the PSFCHtransmissions, determine transmit power for N PSFCHs, and transmit NPSFCHs based on the transmit power. For example, N may be an integer of1 or more. For example, the transmit power related to the PSFCHtransmissions with high priority may be less than or equal to themaximum transmit power of the first UE.

FIG. 15 illustrates a method for a second device to receive N PSFCHsaccording to an embodiment of the present disclosure. The embodiment ofFIG. 15 may be combined with various embodiments of the presentdisclosure.

Referring to FIG. 15, in step S1510, the second device 200 may transmitat least one PSCCH to the first device 100.

In step S1520, the second device 200 may transmit at least one PSSCHrelated to at least one PSCCH to the first device 100. For example, thesecond device 200 may determine a resource related to at least one PSFCHbased on an index of a slot and an index of a subchannel related to theat least one PSSCH.

For example, based on the at least one PSSCH overlapping with the firstchannel and the second channel in the time domain, at least one of theat least one PSSCH, the first channel, or the second channel may beomitted. For example, the first channel may lead the most in the timedomain and the second channel may trail the most in the time domain. Forexample, among priorities related to channels, the priority related tothe first channel may be the lowest, and the priority related to thesecond channel may be the highest. In this case, for example, based onthe priority related to the second channel not being identified, thefirst channel and the second channel may be omitted regardless of thepriority related to the channels. Or, for example, based on the priorityrelated to the second channel not being identified by the MAC layer,information on the priority related to the second channel may betransmitted from the PHY layer to the MAC layer. In this case, forexample, at least one PSSCH may be omitted based on the information onpriority related to the second channel.

For example, at least one PSSCH may include at least one SCI. Forexample, the number of Resource Elements (REs) used to map at least oneSCI may be calculated. For example, the calculation of the number of REsmay be performed without considering an overhead related to apre-configured SL CSI-RS. For example, the size of a transport blockrelated to at least one PSSCH may be determined based on an indicatorrelated to a PSFCH overhead. For example, the Cyclic Redundancy Check(CRC) related to the at least one SCI may include an indicator relatedto the PSFCH overhead.

For example, the overhead related to at least one PSFCH resource may notbe used for derivation of sidelink CSI information. For example, thesidelink CSI information may be derived on a reference resource relatedto the sidelink CSI. For example, the reference resource related to thesidelink CSI may be a sidelink slot in which at least one of a PSCCH ora PSSCH triggering a sidelink SCI report is received. For example, thereference resource related to the sidelink CSI may be a PhysicalResource Block (PRB) related to the PSSCH triggering the sidelink CSIreport.

In step S1530, the second device 200 may receive N PSFCHs from the firstdevice 100. For example, based on the sum of power required for the atleast one PSFCH being greater than the maximum transmit power of thefirst device 100, N PSFCHs from among the at least one PSFCH may bedetermined by the first device 100. For example, N may be selected fromthe number of PSFCH transmissions with high priority among the maximumnumber of PSFCH transmissions to the maximum number of PSFCHtransmissions. For example, N may be an integer of 1 or more. Forexample, the transmit power related to PSFCH transmission having a highpriority may be less than or equal to the maximum transmit power of thefirst device 100. For example, based on the number of PSFCHs scheduledto the first device 100 being greater than the maximum number of PSFCHsthat the first device 100 can transmit, the maximum number of PSFCHtransmissions may be the maximum number of PSFCHs that the first device100 can transmit. For example, based on the number of PSFCHs scheduledto the first device 100 being smaller than the maximum number of PSFCHsthat the first device 100 can transmit, the maximum number of PSFCHtransmissions may be the number of PSFCHs scheduled to the first device100. For example, N may be autonomously selected by the first device100. For example, the transmit power value of each of the N PSFCHs maybe a value in which the maximum transmit power value of the first device100 is equally shared.

For example, based on parameters related to Open Loop Power Control(OLPC) that determines the transmit power for the PSFCH being notconfigured to the first device 100, the transmit power for the PSFCH maybe configured to a maximum transmit power value of the first device 100.

The above-described embodiment may be applied to various devices to bedescribed below. For example, the processor 202 of the second device 200may control the transceiver 206 to transmit at least one PSCCH to thefirst device 100. In addition, the processor 202 of the second device200 may control the transceiver 206 to transmit at least one PSSCHrelated to the at least one PSCCH to the first device 100. In addition,the processor 202 of the second device 200 may control the transceiver206 to receive N PSFCHs from the first device 100.

According to an embodiment of the present disclosure, a second devicefor performing wireless communication may be provided. For example, thesecond device may include one or more memories for storing instructions;one or more transceivers; and one or more processors connecting the oneor more memories and the one or more transceivers. For example, the oneor more processors may execute the instructions to transmit at least onephysical sidelink control channel (PSCCH) to the first device, transmitat least one physical sidelink shared channel (PSSCH) related to the atleast one PSCCH to the first device, determine a resource related to atleast one physical sidelink feedback channel (PSFCH) based on the indexof the slot and the index of the subchannel related to the at least onePSSCH, and receive N PSFCHs from the first device. For example, based onthe sum of power required for the at least one PSFCH being greater thanthe maximum transmit power of the first device, N PSFCHs among the atleast one PSFCH may be determined by the first device. For example, Nmay be selected from the number of PSFCH transmissions having a highpriority among the maximum number of PSFCH transmissions to the maximumnumber of PSFCH transmissions. For example, N may be an integer of 1 ormore. For example, the transmit power related to the PSFCH transmissionshaving a high priority may be less than or equal to the maximum transmitpower of the first device.

Various embodiments of the present disclosure may be combined with eachother.

Hereinafter, device(s) to which various embodiments of the presentdisclosure can be applied will be described.

The various descriptions, functions, procedures, proposals, methods,and/or operational flowcharts of the present disclosure described inthis document may be applied to, without being limited to, a variety offields requiring wireless communication/connection (e.g., 5G) betweendevices.

Hereinafter, a description will be given in more detail with referenceto the drawings. In the following drawings/description, the samereference symbols may denote the same or corresponding hardware blocks,software blocks, or functional blocks unless described otherwise.

FIG. 16 shows a communication system 1, based on an embodiment of thepresent disclosure.

Referring to FIG. 16, a communication system 1 to which variousembodiments of the present disclosure are applied includes wirelessdevices, Base Stations (BSs), and a network. Herein, the wirelessdevices represent devices performing communication using Radio AccessTechnology (RAT) (e.g., 5G New RAT (NR)) or Long-Term Evolution (LTE))and may be referred to as communication/radio/5G devices. The wirelessdevices may include, without being limited to, a robot 100 a, vehicles100 b-1 and 100 b-2, an eXtended Reality (XR) device 100 c, a hand-helddevice 100 d, a home appliance 100 e, an Internet of Things (IoT) device100 f, and an Artificial Intelligence (AI) device/server 400. Forexample, the vehicles may include a vehicle having a wirelesscommunication function, an autonomous vehicle, and a vehicle capable ofperforming communication between vehicles. Herein, the vehicles mayinclude an Unmanned Aerial Vehicle (UAV) (e.g., a drone). The XR devicemay include an Augmented Reality (AR)/Virtual Reality (VR)/Mixed Reality(MR) device and may be implemented in the form of a Head-Mounted Device(HMD), a Head-Up Display (HUD) mounted in a vehicle, a television, asmartphone, a computer, a wearable device, a home appliance device, adigital signage, a vehicle, a robot, etc. The hand-held device mayinclude a smartphone, a smartpad, a wearable device (e.g., a smartwatchor a smartglasses), and a computer (e.g., a notebook). The homeappliance may include a TV, a refrigerator, and a washing machine. TheIoT device may include a sensor and a smartmeter. For example, the BSsand the network may be implemented as wireless devices and a specificwireless device 200 a may operate as a BS/network node with respect toother wireless devices.

Here, wireless communication technology implemented in wireless devices100 a to 100 f of the present disclosure may include Narrowband Internetof Things for low-power communication in addition to LTE, NR, and 6G. Inthis case, for example, NB-IoT technology may be an example of Low PowerWide Area Network (LPWAN) technology and may be implemented as standardssuch as LTE Cat NB1, and/or LTE Cat NB2, and is not limited to the namedescribed above. Additionally or alternatively, the wirelesscommunication technology implemented in the wireless devices 100 a to100 f of the present disclosure may perform communication based on LTE-Mtechnology. In this case, as an example, the LTE-M technology may be anexample of the LPWAN and may be called by various names includingenhanced Machine Type Communication (eMTC), and the like. For example,the LTE-M technology may be implemented as at least any one of variousstandards such as 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTEnon-Bandwidth Limited (non-BL), 5) LTE-MTC, 6) LTE Machine TypeCommunication, and/or 7) LTE M, and is not limited to the name describedabove. Additionally or alternatively, the wireless communicationtechnology implemented in the wireless devices 100 a to 100 f of thepresent disclosure may include at least one of Bluetooth, Low Power WideArea Network (LPWAN), and ZigBee considering the low-powercommunication, and is not limited to the name described above. As anexample, the ZigBee technology may generate personal area networks (PAN)related to small/low-power digital communication based on variousstandards including IEEE 802.15.4, and the like, and may be called byvarious names.

The wireless devices 100 a to 100 f may be connected to the network 300via the BSs 200. An AI technology may be applied to the wireless devices100 a to 100 f and the wireless devices 100 a to 100 f may be connectedto the AI server 400 via the network 300. The network 300 may beconfigured using a 3G network, a 4G (e.g., LTE) network, or a 5G (e.g.,NR) network. Although the wireless devices 100 a to 100 f maycommunicate with each other through the BSs 200/network 300, thewireless devices 100 a to 100 f may perform direct communication (e.g.,sidelink communication) with each other without passing through theBSs/network. For example, the vehicles 100 b-1 and 100 b-2 may performdirect communication (e.g. Vehicle-to-Vehicle(V2V)/Vehicle-to-everything (V2X) communication). The IoT device (e.g.,a sensor) may perform direct communication with other IoT devices (e.g.,sensors) or other wireless devices 100 a to 100 f.

Wireless communication/connections 150 a, 150 b, or 150 c may beestablished between the wireless devices 100 a to 100 f/BS 200, or BS200/BS 200. Herein, the wireless communication/connections may beestablished through various RATs (e.g., 5G NR) such as uplink/downlinkcommunication 150 a, sidelink communication 150 b (or, D2Dcommunication), or inter BS communication (e.g. relay, Integrated AccessBackhaul (IAB)). The wireless devices and the BSs/the wireless devicesmay transmit/receive radio signals to/from each other through thewireless communication/connections 150 a and 150 b. For example, thewireless communication/connections 150 a and 150 b may transmit/receivesignals through various physical channels. To this end, at least a partof various configuration information configuring processes, varioussignal processing processes (e.g., channel encoding/decoding,modulation/demodulation, and resource mapping/demapping), and resourceallocating processes, for transmitting/receiving radio signals, may beperformed based on the various proposals of the present disclosure.

FIG. 17 shows wireless devices, based on an embodiment of the presentdisclosure.

Referring to FIG. 17, a first wireless device 100 and a second wirelessdevice 200 may transmit radio signals through a variety of RATs (e.g.,LTE and NR). Herein, {the first wireless device 100 and the secondwireless device 200} may correspond to {the wireless device 100 x andthe BS 200} and/or {the wireless device 100 x and the wireless device100 x} of FIG. 16.

The first wireless device 100 may include one or more processors 102 andone or more memories 104 and additionally further include one or moretransceivers 106 and/or one or more antennas 108. The processor(s) 102may control the memory(s) 104 and/or the transceiver(s) 106 and may beconfigured to implement the descriptions, functions, procedures,proposals, methods, and/or operational flowcharts disclosed in thisdocument. For example, the processor(s) 102 may process informationwithin the memory(s) 104 to generate first information/signals and thentransmit radio signals including the first information/signals throughthe transceiver(s) 106. The processor(s) 102 may receive radio signalsincluding second information/signals through the transceiver 106 andthen store information obtained by processing the secondinformation/signals in the memory(s) 104. The memory(s) 104 may beconnected to the processor(s) 102 and may store a variety of informationrelated to operations of the processor(s) 102. For example, thememory(s) 104 may store software code including commands for performinga part or the entirety of processes controlled by the processor(s) 102or for performing the descriptions, functions, procedures, proposals,methods, and/or operational flowcharts disclosed in this document.Herein, the processor(s) 102 and the memory(s) 104 may be a part of acommunication modem/circuit/chip designed to implement RAT (e.g., LTE orNR). The transceiver(s) 106 may be connected to the processor(s) 102 andtransmit and/or receive radio signals through one or more antennas 108.Each of the transceiver(s) 106 may include a transmitter and/or areceiver. The transceiver(s) 106 may be interchangeably used with RadioFrequency (RF) unit(s). In the present disclosure, the wireless devicemay represent a communication modem/circuit/chip.

The second wireless device 200 may include one or more processors 202and one or more memories 204 and additionally further include one ormore transceivers 206 and/or one or more antennas 208. The processor(s)202 may control the memory(s) 204 and/or the transceiver(s) 206 and maybe configured to implement the descriptions, functions, procedures,proposals, methods, and/or operational flowcharts disclosed in thisdocument. For example, the processor(s) 202 may process informationwithin the memory(s) 204 to generate third information/signals and thentransmit radio signals including the third information/signals throughthe transceiver(s) 206. The processor(s) 202 may receive radio signalsincluding fourth information/signals through the transceiver(s) 106 andthen store information obtained by processing the fourthinformation/signals in the memory(s) 204. The memory(s) 204 may beconnected to the processor(s) 202 and may store a variety of informationrelated to operations of the processor(s) 202. For example, thememory(s) 204 may store software code including commands for performinga part or the entirety of processes controlled by the processor(s) 202or for performing the descriptions, functions, procedures, proposals,methods, and/or operational flowcharts disclosed in this document.Herein, the processor(s) 202 and the memory(s) 204 may be a part of acommunication modem/circuit/chip designed to implement RAT (e.g., LTE orNR). The transceiver(s) 206 may be connected to the processor(s) 202 andtransmit and/or receive radio signals through one or more antennas 208.Each of the transceiver(s) 206 may include a transmitter and/or areceiver. The transceiver(s) 206 may be interchangeably used with RFunit(s). In the present disclosure, the wireless device may represent acommunication modem/circuit/chip.

Hereinafter, hardware elements of the wireless devices 100 and 200 willbe described more specifically. One or more protocol layers may beimplemented by, without being limited to, one or more processors 102 and202. For example, the one or more processors 102 and 202 may implementone or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP,RRC, and SDAP). The one or more processors 102 and 202 may generate oneor more Protocol Data Units (PDUs) and/or one or more Service Data Unit(SDUs) according to the descriptions, functions, procedures, proposals,methods, and/or operational flowcharts disclosed in this document. Theone or more processors 102 and 202 may generate messages, controlinformation, data, or information according to the descriptions,functions, procedures, proposals, methods, and/or operational flowchartsdisclosed in this document. The one or more processors 102 and 202 maygenerate signals (e.g., baseband signals) including PDUs, SDUs,messages, control information, data, or information according to thedescriptions, functions, procedures, proposals, methods, and/oroperational flowcharts disclosed in this document and provide thegenerated signals to the one or more transceivers 106 and 206. The oneor more processors 102 and 202 may receive the signals (e.g., basebandsignals) from the one or more transceivers 106 and 206 and acquire thePDUs, SDUs, messages, control information, data, or informationaccording to the descriptions, functions, procedures, proposals,methods, and/or operational flowcharts disclosed in this document.

The one or more processors 102 and 202 may be referred to ascontrollers, microcontrollers, microprocessors, or microcomputers. Theone or more processors 102 and 202 may be implemented by hardware,firmware, software, or a combination thereof. As an example, one or moreApplication Specific Integrated Circuits (ASICs), one or more DigitalSignal Processors (DSPs), one or more Digital Signal Processing Devices(DSPDs), one or more Programmable Logic Devices (PLDs), or one or moreField Programmable Gate Arrays (FPGAs) may be included in the one ormore processors 102 and 202. The descriptions, functions, procedures,proposals, methods, and/or operational flowcharts disclosed in thisdocument may be implemented using firmware or software and the firmwareor software may be configured to include the modules, procedures, orfunctions. Firmware or software configured to perform the descriptions,functions, procedures, proposals, methods, and/or operational flowchartsdisclosed in this document may be included in the one or more processors102 and 202 or stored in the one or more memories 104 and 204 so as tobe driven by the one or more processors 102 and 202. The descriptions,functions, procedures, proposals, methods, and/or operational flowchartsdisclosed in this document may be implemented using firmware or softwarein the form of code, commands, and/or a set of commands.

The one or more memories 104 and 204 may be connected to the one or moreprocessors 102 and 202 and store various types of data, signals,messages, information, programs, code, instructions, and/or commands.The one or more memories 104 and 204 may be configured by Read-OnlyMemories (ROMs), Random Access Memories (RAMs), Electrically ErasableProgrammable Read-Only Memories (EPROMs), flash memories, hard drives,registers, cash memories, computer-readable storage media, and/orcombinations thereof. The one or more memories 104 and 204 may belocated at the interior and/or exterior of the one or more processors102 and 202. The one or more memories 104 and 204 may be connected tothe one or more processors 102 and 202 through various technologies suchas wired or wireless connection.

The one or more transceivers 106 and 206 may transmit user data, controlinformation, and/or radio signals/channels, mentioned in the methodsand/or operational flowcharts of this document, to one or more otherdevices. The one or more transceivers 106 and 206 may receive user data,control information, and/or radio signals/channels, mentioned in thedescriptions, functions, procedures, proposals, methods, and/oroperational flowcharts disclosed in this document, from one or moreother devices. For example, the one or more transceivers 106 and 206 maybe connected to the one or more processors 102 and 202 and transmit andreceive radio signals. For example, the one or more processors 102 and202 may perform control so that the one or more transceivers 106 and 206may transmit user data, control information, or radio signals to one ormore other devices. The one or more processors 102 and 202 may performcontrol so that the one or more transceivers 106 and 206 may receiveuser data, control information, or radio signals from one or more otherdevices. The one or more transceivers 106 and 206 may be connected tothe one or more antennas 108 and 208 and the one or more transceivers106 and 206 may be configured to transmit and receive user data, controlinformation, and/or radio signals/channels, mentioned in thedescriptions, functions, procedures, proposals, methods, and/oroperational flowcharts disclosed in this document, through the one ormore antennas 108 and 208. In this document, the one or more antennasmay be a plurality of physical antennas or a plurality of logicalantennas (e.g., antenna ports). The one or more transceivers 106 and 206may convert received radio signals/channels etc. from RF band signalsinto baseband signals in order to process received user data, controlinformation, radio signals/channels, etc. using the one or moreprocessors 102 and 202. The one or more transceivers 106 and 206 mayconvert the user data, control information, radio signals/channels, etc.processed using the one or more processors 102 and 202 from the baseband signals into the RF band signals. To this end, the one or moretransceivers 106 and 206 may include (analog) oscillators and/orfilters.

FIG. 18 shows a signal process circuit for a transmission signal, basedon an embodiment of the present disclosure.

Referring to FIG. 18, a signal processing circuit 1000 may includescramblers 1010, modulators 1020, a layer mapper 1030, a precoder 1040,resource mappers 1050, and signal generators 1060. An operation/functionof FIG. 18 may be performed, without being limited to, the processors102 and 202 and/or the transceivers 106 and 206 of FIG. 17. Hardwareelements of FIG. 18 may be implemented by the processors 102 and 202and/or the transceivers 106 and 206 of FIG. 17. For example, blocks 1010to 1060 may be implemented by the processors 102 and 202 of FIG. 17.Alternatively, the blocks 1010 to 1050 may be implemented by theprocessors 102 and 202 of FIG. 17 and the block 1060 may be implementedby the transceivers 106 and 206 of FIG. 17.

Codewords may be converted into radio signals via the signal processingcircuit 1000 of FIG. 18. Herein, the codewords are encoded bit sequencesof information blocks. The information blocks may include transportblocks (e.g., a UL-SCH transport block, a DL-SCH transport block). Theradio signals may be transmitted through various physical channels(e.g., a PUSCH and a PDSCH).

Specifically, the codewords may be converted into scrambled bitsequences by the scramblers 1010. Scramble sequences used for scramblingmay be generated based on an initialization value, and theinitialization value may include ID information of a wireless device.The scrambled bit sequences may be modulated to modulation symbolsequences by the modulators 1020. A modulation scheme may includepi/2-Binary Phase Shift Keying (pi/2-BPSK), m-Phase Shift Keying(m-PSK), and m-Quadrature Amplitude Modulation (m-QAM). Complexmodulation symbol sequences may be mapped to one or more transportlayers by the layer mapper 1030. Modulation symbols of each transportlayer may be mapped (precoded) to corresponding antenna port(s) by theprecoder 1040. Outputs z of the precoder 1040 may be obtained bymultiplying outputs y of the layer mapper 1030 by an N*M precodingmatrix W. Herein, N is the number of antenna ports and M is the numberof transport layers. The precoder 1040 may perform precoding afterperforming transform precoding (e.g., DFT) for complex modulationsymbols. Alternatively, the precoder 1040 may perform precoding withoutperforming transform precoding.

The resource mappers 1050 may map modulation symbols of each antennaport to time-frequency resources. The time-frequency resources mayinclude a plurality of symbols (e.g., a CP-OFDMA symbols and DFT-s-OFDMAsymbols) in the time domain and a plurality of subcarriers in thefrequency domain. The signal generators 1060 may generate radio signalsfrom the mapped modulation symbols and the generated radio signals maybe transmitted to other devices through each antenna. For this purpose,the signal generators 1060 may include Inverse Fast Fourier Transform(IFFT) modules, Cyclic Prefix (CP) inserters, Digital-to-AnalogConverters (DACs), and frequency up-converters.

Signal processing procedures for a signal received in the wirelessdevice may be configured in a reverse manner of the signal processingprocedures 1010 to 1060 of FIG. 18. For example, the wireless devices(e.g., 100 and 200 of FIG. 17) may receive radio signals from theexterior through the antenna ports/transceivers. The received radiosignals may be converted into baseband signals through signal restorers.To this end, the signal restorers may include frequency downlinkconverters, Analog-to-Digital Converters (ADCs), CP remover, and FastFourier Transform (FFT) modules. Next, the baseband signals may berestored to codewords through a resource demapping procedure, apostcoding procedure, a demodulation processor, and a descramblingprocedure. The codewords may be restored to original information blocksthrough decoding. Therefore, a signal processing circuit (notillustrated) for a reception signal may include signal restorers,resource demappers, a postcoder, demodulators, descramblers, anddecoders.

FIG. 19 shows another example of a wireless device, based on anembodiment of the present disclosure. The wireless device may beimplemented in various forms according to a use-case/service (refer toFIG. 16).

Referring to FIG. 19, wireless devices 100 and 200 may correspond to thewireless devices 100 and 200 of FIG. 17 and may be configured by variouselements, components, units/portions, and/or modules. For example, eachof the wireless devices 100 and 200 may include a communication unit110, a control unit 120, a memory unit 130, and additional components140. The communication unit may include a communication circuit 112 andtransceiver(s) 114. For example, the communication circuit 112 mayinclude the one or more processors 102 and 202 and/or the one or morememories 104 and 204 of FIG. 17. For example, the transceiver(s) 114 mayinclude the one or more transceivers 106 and 206 and/or the one or moreantennas 108 and 208 of FIG. 17. The control unit 120 is electricallyconnected to the communication unit 110, the memory 130, and theadditional components 140 and controls overall operation of the wirelessdevices. For example, the control unit 120 may control anelectric/mechanical operation of the wireless device based onprograms/code/commands/information stored in the memory unit 130. Thecontrol unit 120 may transmit the information stored in the memory unit130 to the exterior (e.g., other communication devices) via thecommunication unit 110 through a wireless/wired interface or store, inthe memory unit 130, information received through the wireless/wiredinterface from the exterior (e.g., other communication devices) via thecommunication unit 110.

The additional components 140 may be variously configured according totypes of wireless devices. For example, the additional components 140may include at least one of a power unit/battery, input/output (I/O)unit, a driving unit, and a computing unit. The wireless device may beimplemented in the form of, without being limited to, the robot (100 aof FIG. 16), the vehicles (100 b-1 and 100 b-2 of FIG. 16), the XRdevice (100 c of FIG. 16), the hand-held device (100 d of FIG. 16), thehome appliance (100 e of FIG. 16), the IoT device (100 f of FIG. 16), adigital broadcast terminal, a hologram device, a public safety device,an MTC device, a medicine device, a fintech device (or a financedevice), a security device, a climate/environment device, the AIserver/device (400 of FIG. 16), the BSs (200 of FIG. 16), a networknode, etc. The wireless device may be used in a mobile or fixed placeaccording to a use-example/service.

In FIG. 19, the entirety of the various elements, components,units/portions, and/or modules in the wireless devices 100 and 200 maybe connected to each other through a wired interface or at least a partthereof may be wirelessly connected through the communication unit 110.For example, in each of the wireless devices 100 and 200, the controlunit 120 and the communication unit 110 may be connected by wire and thecontrol unit 120 and first units (e.g., 130 and 140) may be wirelesslyconnected through the communication unit 110. Each element, component,unit/portion, and/or module within the wireless devices 100 and 200 mayfurther include one or more elements. For example, the control unit 120may be configured by a set of one or more processors. As an example, thecontrol unit 120 may be configured by a set of a communication controlprocessor, an application processor, an Electronic Control Unit (ECU), agraphical processing unit, and a memory control processor. As anotherexample, the memory 130 may be configured by a Random Access Memory(RAM), a Dynamic RAM (DRAM), a Read Only Memory (ROM)), a flash memory,a volatile memory, a non-volatile memory, and/or a combination thereof.

Hereinafter, an example of implementing FIG. 19 will be described indetail with reference to the drawings.

FIG. 20 shows a hand-held device, based on an embodiment of the presentdisclosure. The hand-held device may include a smartphone, a smartpad, awearable device (e.g., a smartwatch or a smartglasses), or a portablecomputer (e.g., a notebook). The hand-held device may be referred to asa mobile station (MS), a user terminal (UT), a Mobile Subscriber Station(MSS), a Subscriber Station (SS), an Advanced Mobile Station (AMS), or aWireless Terminal (WT).

Referring to FIG. 20, a hand-held device 100 may include an antenna unit108, a communication unit 110, a control unit 120, a memory unit 130, apower supply unit 140 a, an interface unit 140 b, and an I/O unit 140 c.The antenna unit 108 may be configured as a part of the communicationunit 110. Blocks 110 to 130/140 a to 140 c correspond to the blocks 110to 130/140 of FIG. 19, respectively.

The communication unit 110 may transmit and receive signals (e.g., dataand control signals) to and from other wireless devices or BSs. Thecontrol unit 120 may perform various operations by controllingconstituent elements of the hand-held device 100. The control unit 120may include an Application Processor (AP). The memory unit 130 may storedata/parameters/programs/code/commands needed to drive the hand-helddevice 100. The memory unit 130 may store input/output data/information.The power supply unit 140 a may supply power to the hand-held device 100and include a wired/wireless charging circuit, a battery, etc. Theinterface unit 140 b may support connection of the hand-held device 100to other external devices. The interface unit 140 b may include variousports (e.g., an audio I/O port and a video I/O port) for connection withexternal devices. The I/O unit 140 c may input or output videoinformation/signals, audio information/signals, data, and/or informationinput by a user. The I/O unit 140 c may include a camera, a microphone,a user input unit, a display unit 140 d, a speaker, and/or a hapticmodule.

As an example, in the case of data communication, the I/O unit 140 c mayacquire information/signals (e.g., touch, text, voice, images, or video)input by a user and the acquired information/signals may be stored inthe memory unit 130. The communication unit 110 may convert theinformation/signals stored in the memory into radio signals and transmitthe converted radio signals to other wireless devices directly or to aBS. The communication unit 110 may receive radio signals from otherwireless devices or the BS and then restore the received radio signalsinto original information/signals. The restored information/signals maybe stored in the memory unit 130 and may be output as various types(e.g., text, voice, images, video, or haptic) through the I/O unit 140c.

FIG. 21 shows a vehicle or an autonomous vehicle, based on an embodimentof the present disclosure. The vehicle or autonomous vehicle may beimplemented by a mobile robot, a car, a train, a manned/unmanned AerialVehicle (AV), a ship, etc.

Referring to FIG. 21, a vehicle or autonomous vehicle 100 may include anantenna unit 108, a communication unit 110, a control unit 120, adriving unit 140 a, a power supply unit 140 b, a sensor unit 140 c, andan autonomous driving unit 140 d. The antenna unit 108 may be configuredas a part of the communication unit 110. The blocks 110/130/140 a to 140d correspond to the blocks 110/130/140 of FIG. 19, respectively.

The communication unit 110 may transmit and receive signals (e.g., dataand control signals) to and from external devices such as othervehicles, BSs (e.g., gNBs and road side units), and servers. The controlunit 120 may perform various operations by controlling elements of thevehicle or the autonomous vehicle 100. The control unit 120 may includean Electronic Control Unit (ECU). The driving unit 140 a may cause thevehicle or the autonomous vehicle 100 to drive on a road. The drivingunit 140 a may include an engine, a motor, a powertrain, a wheel, abrake, a steering device, etc. The power supply unit 140 b may supplypower to the vehicle or the autonomous vehicle 100 and include awired/wireless charging circuit, a battery, etc. The sensor unit 140 cmay acquire a vehicle state, ambient environment information, userinformation, etc. The sensor unit 140 c may include an InertialMeasurement Unit (IMU) sensor, a collision sensor, a wheel sensor, aspeed sensor, a slope sensor, a weight sensor, a heading sensor, aposition module, a vehicle forward/backward sensor, a battery sensor, afuel sensor, a tire sensor, a steering sensor, a temperature sensor, ahumidity sensor, an ultrasonic sensor, an illumination sensor, a pedalposition sensor, etc. The autonomous driving unit 140 d may implementtechnology for maintaining a lane on which a vehicle is driving,technology for automatically adjusting speed, such as adaptive cruisecontrol, technology for autonomously driving along a determined path,technology for driving by automatically setting a path if a destinationis set, and the like.

For example, the communication unit 110 may receive map data, trafficinformation data, etc. from an external server. The autonomous drivingunit 140 d may generate an autonomous driving path and a driving planfrom the obtained data. The control unit 120 may control the drivingunit 140 a such that the vehicle or the autonomous vehicle 100 may movealong the autonomous driving path according to the driving plan (e.g.,speed/direction control). In the middle of autonomous driving, thecommunication unit 110 may aperiodically/periodically acquire recenttraffic information data from the external server and acquiresurrounding traffic information data from neighboring vehicles. In themiddle of autonomous driving, the sensor unit 140 c may obtain a vehiclestate and/or surrounding environment information. The autonomous drivingunit 140 d may update the autonomous driving path and the driving planbased on the newly obtained data/information. The communication unit 110may transfer information about a vehicle position, the autonomousdriving path, and/or the driving plan to the external server. Theexternal server may predict traffic information data using AItechnology, etc., based on the information collected from vehicles orautonomous vehicles and provide the predicted traffic information datato the vehicles or the autonomous vehicles.

Claims in the present description can be combined in a various way. Forinstance, technical features in method claims of the present descriptioncan be combined to be implemented or performed in an apparatus, andtechnical features in apparatus claims can be combined to be implementedor performed in a method. Further, technical features in method claim(s)and apparatus claim(s) can be combined to be implemented or performed inan apparatus. Further, technical features in method claim(s) andapparatus claim(s) can be combined to be implemented or performed in amethod.

The present disclosure may operate based on Tables 5 to 7 below.

TABLE 5 When the UE supports up to Nmax,psfch simultaneous PSFCHtransmissions in a PSFCH TX occasion and UE have Nreq PSFCHs to betransmitted in a given PSFCH TX occasion, the UE selects N PSFCHs foractual transmission with ascending order of the priority in a PSFCH TXoccasion as follows: Case 1: When NreqK<-Nmax,psfch and P_(O,PSFCH) is(pre-)configured,  Case 1-1: N = Nreq if the sum of P_(O,PSFCH) + 101og₁₀(2^(μ)) + α_(PFSCH) · PL for the  Nreq PSFCHs is smaller than orequal to P_(CMAX) determined for the Nreq PSFCH  transmissions.  Case1-2: Otherwise, N is up to UE implementation under N >= X >= 1.

Table 5 shows a method for the UE to select N PSFCHs based on prioritywhen the number of PSFCH transmissions required for the UE is less thanor equal to the number of PSFCH transmissions that can be transmittedsimultaneously.

TABLE 6 Case 2: When Nrea>Nmax,psfch and P_(O,PSFCH) is(pre-)configured, the UE firstly selects Nmax,psfch PSFCHs withascending order of the priority.  Case 2-1: N=Nmax,psfch if the sum ofP_(O,PSFCH) +10log₁₀(2^(μ)) + α_(PFSCH) · PL for  the Nmax,psfch PSFCHsis smaller than or equal to P_(CMAX) determined for the  Nmax,psfchPSFCH transmissions.  Case 2-2: Otherwise, N is up to UE implementationunder N > = X >= 1. Down select X in RAN1# 101-e  Alt 1: X = max {1, thelargest value which doesn lead to the power limited case}  Alt 2: X= 1 Other alternatives are not precluded.

Table 6 shows a method for the UE to select N PSFCHs based on prioritywhen the number of PSFCH transmissions required for the UE is greaterthan the number of PSFCH transmissions that can be transmittedsimultaneously.

TABLE 7 For Case 1-2 and Case 2-2 of simultaneous transmissions ofPSFCH, the lower bound X the number of actually transmitted PSFCH isgiven by X = max (1, Y = M_1 + M_2 + . . . + M_ 

 where  M_i is the number of PSFCHS assigned with the priority value i K is the largest value which does not lead to the power limited casewhen the  

 transmits all the PSFCHs with the priority value 1, 2, ...., K

indicates data missing or illegible when filed

Table 7 shows the contents of the lower bound X, in relation to thesimultaneous PSFCH transmission of cases 1-2 and case 2-2.

What is claimed is:
 1. A method for performing wireless communication bya first device, the method comprising: receiving at least one physicalsidelink control channel (PSCCH); receiving at least one physicalsidelink shared channel (PSSCH) related to the at least one PSCCH;determining a resource related to at least one physical sidelinkfeedback channel (PSFCH) based on an index of a slot and an index of asubchannel related to at least one PSSCH; determining N PSFCHs fromamong the at least one PSFCH based on a sum of power required totransmit the at least one PSFCH being greater than a maximum transmitpower of the first device, wherein N is selected from a number of PSFCHtransmissions with high priority among a maximum number of PSFCHtransmissions, to the maximum number of the PSFCH transmissions;determining a transmit power for the N PSFCHs; and transmitting the NPSFCHs based on the transmit power. wherein N is an integer of 1 ormore, and wherein a transmit power related to the PSFCH transmissionswith high priority is less than or equal to the maximum transmit powerof the first device.
 2. The method of claim 1, wherein, based on anumber of PSFCHs scheduled to the first device being greater than amaximum number of PSFCHs that the first device can transmit, the maximumnumber of PSFCH transmissions is the maximum number of PSFCHs that thefirst device can transmit.
 3. The method of claim 1, wherein, based on anumber of PSFCHs scheduled to the first device being smaller than amaximum number of PSFCHs that the first device can transmit, the maximumnumber of PSFCH transmissions is a number of PSFCHs scheduled to thefirst device.
 4. The method of claim 1, wherein the N is autonomouslyselected by the first device.
 5. The method of claim 1, wherein, basedon parameters related to Open Loop Power Control (OLPC) that determinesa transmit power for a PSFCH being not configured to the first device,the transmit power for the PSFCH is configured to the maximum transmitpower of the first device.
 6. The method of claim 5, wherein thetransmit power of each of the N PSFCHs is a value in which the maximumtransmit power of the first device is equally shared.
 7. The method ofclaim 1, wherein, based on the at least one PSSCH overlapping with afirst channel and a second channel in a time domain, at least one of theat least one PSSCH, the first channel, or the second channel is omitted.wherein the first channel leads the most in the time domain and thesecond channel trails the most in the time domain, and wherein, amongpriorities related to channels, the priority related to the firstchannel is the lowest, and the priority related to the second channel isthe highest.
 8. The method of claim 7, wherein, based on the priorityrelated to the second channel not being identified, the first channeland the second channel are omitted regardless of the priority related tothe channels.
 9. The method of claim 7, wherein, based on the priorityrelated to the second channel not being identified by a MAC layer,information on the priority related to the second channel is transmittedfrom a PHY layer to the MAC layer, and wherein the at least one PSSCH isomitted based on the information on the priority related to the secondchannel.
 10. The method of claim 1, wherein the at least one PSSCHincludes at least one SCI, wherein a number of Resource Elements (REs)used to map the at least one SCI is calculated, and wherein thecalculation of the number of REs is performed without considering anoverhead related to a pre-configured SL channel state information(CSI)-reference signal (RS).
 11. The method of claim 10, wherein a sizeof a transport block related to the at least one PSSCH is determinedbased on an indicator related to a PSFCH overhead, and wherein a CyclicRedundancy Check (CRC) related to the at least one SCI includes theindicator.
 12. The method of claim 1, wherein the overhead related to atleast one PSFCH resource is not used for derivation of sidelink CSIinformation.
 13. The method of claim 12, wherein the sidelink CSIinformation is derived on a reference resource related to the sidelinkCSI, wherein the reference resource related to the sidelink CSI is asidelink slot in which at least one of a PSCCH or a PSSCH triggering asidelink SCI report is received, and wherein the reference resourcerelated to the sidelink CSI is a Physical Resource Block (PRB) relatedto the PSSCH triggering the sidelink CSI report.
 14. A first deviceconfigured to perform wireless communication, the first devicecomprising: one or more memories storing instructions; one or moretransceivers; and one or more processors connected to the one or morememories and the one or more transceivers, wherein the one or moreprocessors execute the instructions to: receive at least one physicalsidelink control channel (PSCCH); receive at least one physical sidelinkshared channel (PS SCH) related to the at least one PSCCH; determine aresource related to at least one physical sidelink feedback channel(PSFCH) based on an index of a slot and an index of a subchannel relatedto at least one PSSCH; determine N PSFCHs from among the at least onePSFCH based on a sum of power required to transmit the at least onePSFCH being greater than a maximum transmit power of the first device,wherein N is selected from a number of PSFCH transmissions with highpriority among a maximum number of PSFCH transmissions, to the maximumnumber of the PSFCH transmissions; determine a transmit power for the NPSFCHs; and transmit the N PSFCHs based on the transmit power. wherein Nis an integer of 1 or more, and wherein a transmit power related to thePSFCH transmissions with high priority is less than or equal to themaximum transmit power of the first device.
 15. The first device ofclaim 14, wherein, based on a number of PSFCHs scheduled to the firstdevice being greater than a maximum number of PSFCHs that the firstdevice can transmit, the maximum number of PSFCH transmissions is themaximum number of PSFCHs that the first device can transmit.
 16. Thefirst device of claim 14, wherein, based on a number of PSFCHs scheduledto the first device being smaller than a maximum number of PSFCHs thatthe first device can transmit, the maximum number of PSFCH transmissionsis a number of PSFCHs scheduled to the first device.
 17. The firstdevice of claim 14, wherein the N is autonomously selected by the firstdevice.
 18. The first device of claim 14, wherein, based on parametersrelated to Open Loop Power Control (OLPC) that determines a transmitpower for a PSFCH being not configured to the first device, the transmitpower for the PSFCH is configured to the maximum transmit power of thefirst device.
 19. The first device of claim 18, wherein the transmitpower of each of the N PSFCHs is a value in which the maximum transmitpower of the first device is equally shared.
 20. An apparatus configuredto control a first user equipment (UE), the apparatus comprising: one ormore processors; and one or more memories operably connected to the oneor more processors and storing instructions, wherein the one or moreprocessors execute the instructions to: receive at least one physicalsidelink control channel (PSCCH); receive at least one physical sidelinkshared channel (PSSCH) related to the at least one PSCCH; determine aresource related to at least one physical sidelink feedback channel(PSFCH) based on an index of a slot and an index of a subchannel relatedto at least one PSSCH; determine N PSFCHs from among the at least onePSFCH based on a sum of power required to transmit the at least onePSFCH being greater than a maximum transmit power of the first device,wherein N is selected from a number of PSFCH transmissions with highpriority among a maximum number of PSFCH transmissions, to the maximumnumber of the PSFCH transmissions; determine a transmit power for the NPSFCHs; and transmit the N PSFCHs based on the transmit power. wherein Nis an integer of 1 or more, and wherein a transmit power related to thePSFCH transmissions with high priority is less than or equal to themaximum transmit power of the first device.